Semi-Complete List of 2-Letter Words and Abbreviations

A

aa - the Hawaiian name for a type of lava; an affirmative reply in Coahuilteco, Inuktitut, Mende, Nepali, Tamil, Telefol, and Tzotzil
áa - an affirmative reply in Blackfoot and Mikmaq
a-a - an affirmative reply in Besisi
?aa - an affirmative reply in Klallam
aA - an attoamprere, which is 10^-18 of an ampere; an abampere, which is ten amperes
AA - an abbreviation for Alcoholics Anonymous, a society designed to get alcoholics off alcohol
ab - a prefix which identifies electrical units as being part of the centimeter-gram-second system
Ab - the chemical symbol for Alabamine, an obsolete name for Astatine
AB - the postal abbreviation for Alberta; a type of blood containing both of two different chemicals
A.B. - Latin artium baccalaureus => Bachelor of Arts, an honorary title
ac - acre, a unit of land area; alternating current, an electrical signal whose intensity varies in a sine wave
aC - an attocoulomb, which is 10^-18 of a coulomb; an abcoulomb, a unit of charge related to the coulomb
Ac - the chemical symbol for Actinium; altocumulus, a cloud type formed of round masses
AC - alternating current, an electrical signal whose intensity varies in a sine wave
A.C. - Latin ante Christum => before christ
-ad - a suffix added to a number to produce a unit of quantity
a.d. - Latin ante diem => before the day
AD - Latin anno domini => year of the lord (Christian calendar)
ae - an affirmative reply in Maori
aé - an affirmative reply in Guaja
'ae - an affirmative reply in Hawaiian and Rarotongan
a'ê - an affirmative reply in Tupi
af - acre foot, a unit of water volume
aF - an attofarad, which is 10^-18 of a farad; an abfarad, a unit of capacitance related to the farad
Af - the symbol for an Afghani, a unit of currency in Afghanistan
AF - the abbreviation for audiofrequency, a frequency that can be heard by humans; a musical abbreviation for the Art of Fugue
ag - an attogram, which is 10^-18 of a gram; an affirmative reply in Auca
Ag - the chemical symbol for Silver
ah - an affirmative reply in Kohistani
aH - an abhenry, a unit of inductance related to the henry
Ah - ampere-hour, a unit of electric charge; in Scottish, a word for 'I'
AH - Latin anno hegirae => year of the Hijri (Islamic calendar)
ai - an affirmative reply in Ndjuka and Sranan
aí - an affirmative reply in Guaja
AI - artificial intelligence, which is quasi-intelligence exhibited by machines
A.I. - Latin anno inventionis => in the year of the discovery
aJ - an attojoule, which is 10^-18 of a joule
aK - an attokelvin, which is 10^-18 of a kelvin
AK - the postal abbreviation for Alaska
al - an attoliter, which is 10^-18 of a liter
al. - Latin alii => other things
aL - an attoliter, which is 10^-18 of a liter
Al - the chemical symbol for Aluminium
AL - the postal abbreviation for Alabama
am - an attometer, which is 10^-18 of a meter; Latin ante meridiem => before noon
Am - the chemical symbol for Americium
A/m - ampere per meter, a unit of magnetic field strength
AM - Latin ante meridiem => before noon; Latin anno mundi => year of the world (Jewish calendar); an abbreviation for amplitude modulation, a type of radio transmission
A.M. - Latin anno mundi => year of the world (Jewish calendar); Latin artium magister => master of arts
an - in Scottish, a word for 'and'
an. - Latin ante => before; Latin anno => year
aN - an attonewton, which is 10^-18 of a newton
An - the chemical symbol for Actinon, an obsolete name for an isotope of Radon
ao - an affirmative reply in Auca and Sasak
Ao - the chemical symbol for Ausonia, an obsolete name for Neptunium
ap - apothecaries', a system of measuring
Ar - the chemical symbol for Argon
Ar. - an abbreviation for Arabic
AR - the postal abbreviation for Arkansas
as - an attosecond, which is 10^-18 of a second; a kind of ancient Roman coin; an arcsecond, a unit of angular measure; a traditional English unit of mass
aS - an abmho, a unit of conductance related to the mho or siemens
As - the chemical symbol for Arsenic; altostratus, a dull grey type of cloud
AS - the postal abbreviation for American Samoa
at - technical atmosphere, a unit of pressure; a rare symbol for an atom; an affirmative reply in Huave
At - ampere turn, a unit of magnetomotive force; the chemical symbol for Astatine
A.t. - an abbreviation for the Atlantic time zone
AT - assay ton, a unit of mass used by minerologists; Latin actus tragicus => tragic act
au - an Astonomical Unit, which is the average radius of Earth's orbit around the sun; an affirmative reply in Gujarati and Miskito
Au - the chemical symbol for Gold
AU - an Astonomical Unit, which is the average radius of Earth's orbit around the sun; absorbance unit, a unit of optical density; animal unit, an American unit of feed consumption by an animal
av - avoirdupois, a system of measuring
aV - an attovolt, which is 10^-18 of a volt; an abvolt, a unit of voltage related to the volt
aw - in Scottish, a word for 'all'; an affirmative reply in Atayal
âw - an affirmative reply in Brahui
àw - an affirmative reply in Gaam
aW - an attowatt, which is 10^-18 of a watt
ay - a variant Scottish affirmative reply; an affirmative reply in Sranan
'ay - an affirmative reply in Tzeltal
Az - the chemical symbol for Azote, an obsolete name for Nitrogen
Az. - an abbreviation for Azerbaijani
AZ - the postal abbreviation for Arizona

B

ba - barye, a unit of pressure; an affirmative reply in Kurdi
Ba - the chemical symbol for Barium
B.A. - Bachelor of Arts, an honorary title; Latin baccalaureus artium => Bachelor of Arts, an honorary title
b/c - an abbreviation for because
BC - an abbreviation for before Christ; the postal abbreviation for British Columbia
Bd - a baud, an engineering unit of data transmission
BD - an abbreviation for a Dinar, a unit of currency
B/D - barrels of oil per day, a unit of the rate of oil pumped from a well
be - an affirmative reply in Mixtec
Be - the chemical symbol for Beryllium; the degree Baume, a scale of relative density
BE - the binding energy, energy in an atom taken from the masses of the particles and used to hold the atom together
bf. - a typographical abbreviation for boldface
BF - board foot, a unit of lumber volume; an abbreviation for the franc, a unit of currency
bg - bougie, a unit equal to either candlepower or a candela
BG - an abbreviation for Brigadier General, a rank in the army
Bh - the chemical symbol for Bohrium
B-H - an abbreviation for Bosnia and Herzegovina
bi- - a prefix meaning two of
Bi - a biot, which is ten amperes; the chemical symbol for Bismuth
Bk - the chemical symbol for Berkelium
bl - barrel, a unit of volume for beer and wine or dry commodities
bm - an abbreviation for board measure
bn - one billion
bo - barrel, a unit of volume for petroleum
b.o. - an abbreviation for buyer's option
bp - a basis point, a proportion equal to a percent of a percent; boiling point, the temperature at which a material turns from a liquid to a gas or vice versa
BP - an abbreviation for years before present; an abbreviation for british petrolium, or gasoline
Bq - a becquerel, which is a unit of radioactivity
Br - the chemical symbol for Bromine
-Br - bromo group
b/s - bits per second, a unit of data transmission
BS - bachelor of sciences, an honorary degree; a symbol for a backspace
bu - bushel, a unit of volume
Bv - the chemical symbol for Brevium, an obsolete name for Protactinium

C

ca - a centiare, which is one ten thousandth of a hectare; Latin circa => about
ca' - in Scottish, a word meaning 'to call'
ca. - Latin circa => about
cA - a centiamprere, which is a hundredth of an ampere
Ca - the chemical symbol for Calcium
CA - cranking amps, a measure of the current supplied by the battery in a car; the postal abbreviation for California
cb - a centibar, a unit of pressure
cb- - a prefix meaning cubic
Cb - the chemical symbol for Columbium, an obsolete name for Niobium; cumulonimbus, a type of cloud with heavy wind that often produces storms
cc - a cubic centimeter, or 10^-6 of a cubic meter; the centesimal second (also ^cc), a tiny unit of radial measure; 200 in roman numerals
cC - a centicoulomb, which is a hundredth of a coulomb
Cc - cirrocumulus, a type of rippling icy high cloud
CC - a symbol for cursor control, an indication that the user should be allowed to control the cursor; 200 in roman numerals
cd - candela, a unit of brightness; cord, a unit of firewood volume; 400 in roman numerals
Cd - the chemical symbol for Cadmium
CD - circular dichroism, the difference in absorption of different frequencies of light by an object; 400 in roman numerals; a compact disk, a method of storing information
ce - a century, which is a hundred years
Ce - the chemical symbol for Cerium
CE - an abbreviation for the Christian era; an abbreviation for the common era; French colonne d'eau => column of water, a unit of pressure
cf - an abbreviation for a cubic foot; Cape foot, a South African unit of distance
cf. - Latin confer => compare
cF - a centifarad, which is a hundredth of a farad
Cf - the chemical symbol for Californium
cg - a centigram, which is a hundredth of a gram
ch - chain, which is 66 feet; a letter of the alphabet in Spanish
ch. - a literary abbreviation for chapter
cH - an abbreviation for a cental, a weight of 100 or 112 pounds
Ch - Charrière gauge, a unit of distance for measuring diameters of small tubes; a French, a small unit of distance equal to the Charrière gauge
CH - the postal abbreviation for Switzerland
ci - 101 in roman numerals
Ci - curie, a unit of radioactivity; an alternate symbol for cirrus, a type of high, wispy cloud
CI - cirrus, a type of high, wispy cloud; 101 in roman numerals
cJ - a centijoule, which is a hundredth of a joule
C.J. - Latin corpus jurus => body of law; an abbreviation for a Chief Justice
cK - a centikelvin, which is a hundredth of a kelvin
cl - a centiliter, which is a hundredth of a liter; 150 in roman numerals
cL - a centiliter, which is a hundredth of a liter
Cl - the chemical symbol for Chlorine
-Cl - chloro group
CL - 150 in roman numerals
cm - a centimeter, which is a hundredth of a meter; 900 in roman numerals
cM - a centimorgan, which is a hundredth of a morgan, which is a unit of genetic separation
Cm - the chemical symbol for Curium
CM - 900 in roman numerals
C.M. - Latin chirurgiæ magister => Master of Surgery
cN - a centinewton, which is a hundredth of a newton
Co - the chemical symbol for Cobalt
Co. - an abbreviation for company, used in company titles
CO - carbon monoxide; the postal abbreviation for Colorado; a commanding officer
-CO- - the carbonyl group in chemistry
cp - candlepower, a unit for measuring light-radiating capacity; a centipoise, a unit of dynamic viscosity
c.p. - an abbreviation meaning chemically pure
cP - a centipoise, which is a hundredth of a poise, which is a unit of dynamic viscosity
Cp - the chemical symbol for Cassiopeium, an obsolete name for Lutetium
cr. - credit; creditor
Cr - the chemical symbol for Chromium
CR - the riel, a unit of currency; a carriage return, which moves the cursor to the beginning of the line
cs - a centisecond, which is a hundredth of a second; a centistoke, one hundredth of a stokes, a unit of kinematic viscosity
cS - an obsolete abbreviation for a centistokes, which is one hundredth of a stokes, which is a unit of kinematic viscosity
Cs - the chemical symbol for Cesium; cirrostratus, a high sheetlike cloud
C.S. - Latin custos sigilli => keeper of the seal, an honorary title
ct - carat, a unit of weight used for gems, which is 200 milligrams; karat, a unit of gold purity; count, a unit of quantity equal to one; an abbreviation for cent
c.t. - an abbreviation for the central time zone
Ct - the chemical symbol for Celtium, an obsolete name for Hafnium
Ct. - an abbreviation for Court
CT - the CT number, equivalent to the Hounsfield unit, a medical unit to describe the amount of X-ray blockage by tissue in a three-dimensional image; the center tap, an electronic practice; the postal abbreviation for Connecticut
cu - an abbreviation for cubic
Cu - the chemical symbol for Copper; cumulus, a common light fluffy cloud
cv - Spanish caballo de vapor, a unit of power equivalent to metric horsepower; French cheval vapeur, a unit of power equivalent to metric horsepower; 105 in roman numerals
cV - a centivolt, which is a hundredth of a volt
CV - 105 in roman numerals
cW - a centiwatt, which is a hundredth of a watt
CW - continuous wave, transmission by way of a single frequency
cx - 110 in roman numerals
CX - 110 in roman numerals
cy - an abbreviation for cubic yard
Cz. - an abbreviation for Czech
CZ - the postal abbreviation for the Canal Zone, the area around the Panama Canal

D

da - a day; an affirmative reply in Bosnian, Bulgarian, Croatian, Karelian, Komi-Zyryan, Macedonian, Romanian, Russian, Serbian, Slovenian, and Votic
da- - the official SI prefix for deka- or deca-, meaning one tenth of
dA - a deciamprere, which is a tenth of an ampere
Da - dalton, a unit of atomic mass equal to the atomic mass unit
DA - a dekamprere, which is ten amperes; an abbreviation for a Dinar, a unit of currency
dB - a decibel, a logarithmic unit of sound intensity
dB- - an indicator of logarithmic scale similar to the decibel but in the unit following the dash
Db - the chemical symbol for Dubnium; the abbreviation for a Dobra, a unit of currency
dc - direct current, an unvarying current of electricity; 600 in roman numerals
dC - a decicoulomb, which is a tenth of a coulomb
DC - a dekacoulomb, which is ten coulombs; the postal abbreviation for the District of Columbia; direct current, an unvarying current of electricity; 600 in roman numerals
Dd - the chemical symbol for Didydium, an obsolete name for either Praseodymium or Neodymium
D.D. - Latin divinitatis doctor => doctor of divinity
De - the deryagin number, a measure of colloid stability
DE - the postal abbreviation for Delaware
dF - a decifarad, which is a tenth of a farad
DF - a dekafarad, which is ten farads
dg - a decigram, which is a tenth of a gram
Dg - a dekagram, which is ten grams
D.G. - Latin Dei gratia => by the grace of God; Latin Deo gratias => thanks to God
DH - an abbreviation for a dirham, a unit of currency
di - 501 in roman numerals; an affirmative reply in Khowar and Wintu
Di - the chemical symbol for Didymium, an obsolete name for either Praseodymium or Neodymium
DI - 501 in roman numerals
dJ - a decijoule, which is a tenth of a joule
DJ - a dekajoule, which is ten joules
dk- - an incorrect abbreviation for deka-, meaning one tenth of
dK - a decikelvin, which is a tenth of a kelvin
DK - a dekakelvin, which is ten kelvins; the postal abbreviation for Denmark
dl - a deciliter, which is a tenth of a liter; 550 in roman numerals
dL - a deciliter, which is a tenth of a liter
Dl - a dekaliter, which is ten liters
DL - a dekaliter, which is ten liters; 550 in roman numerals
dm - a decimeter, which is a tenth of a meter
Dm - a dekameter, which is ten meters
DM - the Deutsche Mark, a German unit of currency
dN - a decinewton, which is a tenth of a newton
DN - a dekanewton, which is ten newtons; nominal diameter, a rating for the inside diameter of pipes and fittings
D.N. - Latin Dominus noster => our Lord
do - an affirmative reply in Welsh
-do - a Korean suffix meaning 'island'
do. - Latin ditto => the same
Dp - the chemical symbol for Decipium, an obsolete name for Samarium
DP - a government abbreviation for a displaced person
dr - dram, which is one sixteenth of a pound
dr. - debit; debtor
Dr - the unit of currency for the Drachma, a Greek unit of currency
Dr. - a standard abbreviation for Doctor; an abbreviation for Drive, used in addresses
ds - a decisecond, which is a tenth of a second; a dash, a small unit of food volume
Ds - a dekasecond, which is ten seconds; the chemical symbol for Darmstadtium
DS - a symbol for digit select, a typographical method for selecting numbers instead of letters
dt - a decitonne, one tenth of a metric tonne, or 100 kilograms
dT - the ton, a unit of ship displacement volume
Dt - the chemical symbol for Dvi-Tellurium, an obsolete name for Polonium
DT - the ton, a unit of ship displacement volume
du - an affirmative reply in Chechen
Du - duplicatus, a variety of cloud in many layers
DU - the Dobson unit, a geophysical unit to measure the amount of ozone in the atmosphere
dv - 505 in roman numerals
dV - a decivolt, which is a tenth of a volt
DV - a dekavolt, which is ten volts; daily value, an American unit of nutrition; 505 in roman numerals
D.V. - Latin Deo volente => if God is willing
dW - a deciwatt, which is a tenth of a watt
DW - a dekawatt, which is ten watts
dx - 510 in roman numerals
DX - 510 in roman numerals; French deluxe => of luxury
Dy - the chemical symbol for Dysprosium
dz - a dozen, a quanity of twelve
Dz - German doppelzentner, a unit of 100 kilograms

E

ea - an affirmative reply in Káte
EA - an examprere, which is 10^18 ampere
EB - the Birr, a unit of currency
EC - an exacoulomb, which is 10^18 coulombs
-ed - in English, a verb suffix used for creating the past tense
ed. - a literary abbreviation for editor
ED - the effective dose, the dose of a medecine that will benefit a certain percent of a population
ee - an affirmative reply in Arabic, Awa, Chinwanja, Ekegusii, Fulani, Icetot, Kachcha, Kiluba, Kipsigis, Luo, Masai, Rapanui, Sepedi, Sesotho, Setswana, and Yao
eè - an affirmative reply in Asante
eé - an affirmative reply in Shuar
ée - an affirmative reply in Lingala
èé - an affirmative reply in Twi
e'e - an affirmative reply in Mikmak and Wali
ee' - an affirmative reply in Wik-mungkan
e-e - an affirmative reply in Awakabal and Lenape
EF - an exafarad, which is 10^18 farads; the energy factor, a measure of an appliance's energy efficiency
e.g. - Latin exempli gratia => for the sake of example
Eg - an exagram, which is 10^18 grams
eh - an affirmative reply in Trobes Tokples
E_h - (also E_h) a unit of energy in physics
Ei- - a prefix for exbi, which means 2^60 of
EJ - an exajoule, which is 10^18 joules
EK - an exakelvin, which is 10^18 kelvins
el - the Dutch ell, a unit of cloth length
El - an exaliter, which is 10^18 liters
EL - an exaliter, which is 10^18 liters
em - a printer's unit measuring the height of the type size
Em - an exameter, which is 10^18 meters
EM - a symbol for end of medium, which identifies the end of the medium used to store information
en - a printer's unit measuring half the height of the type size; an affirmative reply in Pahlavi, Sogdian, and Yoruba
EN - an exanewton, which is 10^18 newtons
eo - an affirmative reply in Breton
Eq - a unit of relative amount in chemistry related to a mole
Er - the chemical symbol for Erbium; in the Bible, Judah's firstborn
ER - electroreflectance, the property of an object that allows it to reflect electric energy; the emergency room; a television show about hospital patients and surgery
Es - an exasecond, which is 10^18 seconds; the chemical symbol for Einsteinium; the chemical symbol for Esperium or Hesperium, obsolete names for Plutonium
e.t. - an abbreviation for the eastern time zone
eu - an affirmative reply in Nauruan
Eu - the chemical symbol for Europium
EU - the enzyme unit, a certain quantity of enzymes; the European Union, an alliance of European countries most of which use the Euro
eV - an electron-volt, which is a unit of electrical energy
EV - an exavolt, which is 10^18 volts; the exposure value, a photographic unit for exposure
EW - an exawatt, which is 10^18 watts
Ex - an abbreviation for the Book of Exodus
Ex. - an abbreviation for the Book of Exodus
-ey - an Icelandic suffix meaning 'island'

F

fA - a femtoamprere, which is 10^-15 of an ampere
Fa - an obsolete chemical symbol for Francium
fc - a footcandle, a unit of illumination
fC - a femtocoulomb, which is 10^-15 of a coulomb
Fd - a faraday, a unit of electric charge
f.e. - an abbreviation for 'for example'
Fe - the chemical symbol for Iron; the quadragesimooctavo, a paper size
ff - Italian fortissimo => very loud
ff. - an abbreviation for 'and following pages'
fF - a femtofarad, which is 10^-15 of a farad
FF - a symbol for form feed, which tells the computer to start on a new sheet of paper
fg - a femtogram, which is 10^-15 of a gram
Fg - a French, a small unit of distance
fJ - a femtojoule, which is 10^-15 of a joule
fK - a femtokelvin, which is 10^-15 of a kelvin
fl - a femtoliter, which is 10^-15 of a liter; foot-lambert, a unit of luminosity; the abbreviation for a guilder, an obsolete Dutch form of currency; an abbreviation for fluid, indicating that a unit measures fluids
fl. - Latin fluidus => fluid; Latin flores => flowers; Latin florius => flourished
fL - foot-lambert, a unit of luminosity; a femtoliter, which is 10^-15 of a liter
Fl - a musical abbreviation for the flute
FL - the postal abbreviation for Florida
fm - a femtometer, which is 10^-15 of a meter; a fermi, an obsolete unit of distance
Fm - the chemical symbol for Fermium
FM - the postal abbreviation for the Federated States of Micronesia; frequency modulation, a type of radio transmission
fN - a femtonewton, which is 10^-15 of a newton
fo - an abbreviation for folio, a paper size
f.r. - Latin folio recto => right page
Fr - a franklin, a unit of electric charge; the chemical symbol for Florentium, an obsolete name for Promethium; the chemical symbol for Francium; an abbreviation for the franc, a unit of currency
Fr. - a standard abbreviation for Father (a member of the Church); an abbreviation for French
FR - an abbreviation for the franc, a unit of currency
fs - a femtosecond, which is 10^-15 of a second
FS - a symbol for a file separator, a control character used to separate successive files; a symbol for a field separator, a control character used to separate units of data; an abbreviation for the forest service
ft - a foot, which is 0.3048 of a meter
Ft - the abbreviation for a florint, a unit of currency
FT - the freight ton, a unit of cargo volume
fu - a flux unit, an astronomical unit of radio signal strength
fu' - in Scottish, a word for either 'full' or 'drunk'
FU - a finsen unit, an obsolete medicinal unit of ultraviolet intensity
f.v. - Latin folio verso => left page
fV - a femtovolt, which is 10^-15 of a volt
fW - a femtowatt, which is 10^-15 of a watt
FZ - an abbreviation for the Franc Zone, formerly a part of the world where francs were used

G

ga - a gauge, a unit for measuring shotgun barrel diameter
Ga - one billion years; the chemical symbol for Gallium
GA - a gigamprere, which is 10^9 amperes; the postal abbreviation for Georgia
Gb - gilbert, a unit of magnetomotive force
GB - a gigabyte, or 2^30 bytes
GC - a gigacoulomb, which is 10^9 coulombs
Gd - the chemical symbol for Gadolinium
Ge - the chemical symbol for Germanium
gf - gram force, an informal unit of weight
GF - a gigafarad, which is 10^9 farads; an abbreviation for the franc, a unit of currency
g/g - gram per gram, a unit of mass concentration
Gg - a gigagram, which is 10^9 grams
gi - a gill, a unit of liquid volume equal to a quarter of a pint
Gi - gilbert, a unit of magnetomotive force
Gi- - a prefix for gibi, which means 2^30 of
GI - an abbreviation for general issue or Government issue
GJ - a gigajoule, which is 10^9 joules
Gk - an abbreviation for Greek
GK - a gigakelvin, which is 10^9 kelvins
Gl - a gigaliter, which is 10^9 liters; the chemical symbol for Glucinium, an obsolete name for Beryllium
GL - a gigaliter, which is 10^9 liters
gm - an incorrect abbreviation for gram
Gm - a gigameter, which is 10^9 meters
g_n - (also g_n) the acceleration due to Earth's gravity, which is 9.80665 meters per square second
GN - a giganewton, which is 10^9 newtons
go - a Japanesse unit of liquid volume
gp - grade point, an American unit of academic recognition
gr - grain, a seven thousandth of a pound; a gross, a quantity of 144; a grad, gon or grade, which is a unit of angular measurement equal to a hundredth of a right angle; the force of gravity
Gs - a gigasecond, which is 10^9 seconds; a gauss, which is a unit of magnetic flux density
GS - a symbol for group separator, a control character used to separate groups of files
gt - an old symbol for a drop, a tiny unit of liquid volume
g/t - grams per tonne, a unit of propotion equal to a part per million (ppm)
Gt - a gigatonne, which is 10^9 metric tons, or 10^15 grams
GT - a green ton or green tonne, which is a ton or tonne of freshly cut timber, which becomes smaller when it dries; a gross ton, which is either 2240 pounds or 100 cubic feet
GU - the postal abbreviation for Guam
GV - a gigavolt, which is 10^9 volts
GW - a gigawatt, which is 10^9 watts
Gy - gray, a unit of absorbed dose of radioactivity

H

ha - a hectare, which is the area of a square 100 meters on a side; an affirmative reply in Armenian, Bengali, Hindi, Nakota, Sindhi, and Urdu
hã - an affirmative reply in Sakai
ha' - an affirmative reply in Chechen and Mono
h.a. - Latin hoc anno => this year
hA - a hectoamprere, which is a hundred amperes
Ha - the chemical symbol for Hahnium, a proposed name for Dubnium or Hassium
HB - Brinell hardness, a unit of the hardness of metal; an abbreviation for the Hebrew Bible, or the Old Testament
hC - a hectocoulomb, which is a hundred coulombs
HC - Hefner candle, an obsolete unit of light intensity
H.C. - the House of Commons
hd - the head, a unit of length or livestock quantity
he - an affirmative reply in Assyrian, Costanoan, Hakka, Ixil, and Totonac
hé - an affirmative reply in Chontal and Dawan
hê - an affirmative reply in Kutenai
hè - an affirmative reply in Wiyot
h.e. - Latin hic est => this is; Latin hoc est => that is
He - the chemical symbol for Helium; a Chinese geographical word meaning 'river'
HE - an abbreviation for high explosive
hF - a hectofarad, which is a hundred farads
Hf - the chemical symbol for Hafnium
HF - high frequency radio (about 27 MHz) used for Citizen Band radio
hg - a hectogram, which is a hundred grams; Italian etto, an informal name for the hectogram
Hg - the chemical symbol for Mercury
HH - a standard abbreviation for His Highness or Her Highness
hi - a casual American greeting
HI - hydrogen iodide; heat index, a measure of the combined effect of heat and humidity on humans; the postal abbreviation for Hawaii
hJ - a hectojoule, which is a hundred joules
hK - a hectokelvin, which is a hundred kelvins
HK - German Hefnerkerze => Hefner candle, which is an obsolete unit of light intensity; Knoop hardness, a measure of the hardness of a metal
hl - a hectoliter, which is a hundred liters; halakim, or helek (halakim is the plural of helek), which is a Hebrew unit of time
hL - a hectoliter, which is a hundred liters
hm - a hectometer, which is a hundred meters; an affirmative reply in Yanomamö
h.m. - Latin hoc mense => in this month
hN - a hectonewton, which is a hundred newtons
ho - an affirmative reply in Chumash, Futuna-Aniya, Georgian, Kashmiri, Muskogee, Nepali, and Wintu
hò - an affirmative reply in Choynok Yokuts
-ho - a Korean suffix meaning 'lake'
Ho - the chemical symbol for Holmium
Hô - the Korean word for reservoir
hp - horsepower, a unit of power
HP - Hewlett-Packard, a computer company
h.q. - Latin hoc quære => look for this
HQ - an abbreviation for headquarters; an accepted height and width of digital videos
hr - an hour
hs - a hectosecond, which is a hundred seconds
h.s. - Latin hoc sensu => in this sense
Hs - the chemical symbol for Hassium
H.S. - Latin hic sepultus => here is buried; Latin hic situs => here lies
h.t. - Latin hoc tempore => at this time; Latin hoc titulo => under this title
HT - the hoppus ton, a British forestry unit of volume; a symbol for horizontal tabulation, a method of aligning text
hu - a Chinese liquid volume unit; an affirmative reply in Cham and Miwok
Hu - the Chinese word for 'lake'
HU - the Hounsfield unit, a medical unit to describe the amount of X-ray blockage by tissue in a three-dimensional image
hV - a hectovolt, which is a hundred volts
HV - the Vickers hardness number, an indicator of the hardness of a metal
hW - a hectowatt, which is a hundred watts
HX - heat index, a measure of the combined effect of heat and humidity on humans
Hz - hertz, a unit of frequency

I

ia - an affirmative reply in Kazakh, Loglan, Pijin, Sakai, Sömañ, Taki-taki, and Yao
IA - the international ångstöm, a unit of length for measuring light wavelengths; the postal abbreviation for Iowa
ib - Latin ibidem => in the same place
ib. - Latin ibidem => in the same place
ic - 99 in roman numerals
IC - 99 in roman numerals
id - in Freudian psychology, the need-fulfillment part of the mind; 499 in roman numerals; an abbreviation for inside diameter
id. - Latin idem => the same
ID - an abbreviation for a Dinar, a unit of currency; the postal abbreviation for Idaho; 499 in roman numerals
ie - an affirmative reply in Welsh
iè - an affirmative reply in Corsican
i.e. - Latin id est => it is
IE - German international einheit => international unit, a unit of the effect of vitamins and drugs
IF - a radio abbreviation for intermediate frequency
IG - the Imperial gallon, a unit of volume
ih - an inhour, a unit for the reactivity of a nuclear reactor; an affirmative reply in Kabyle, Sema, and Venda
ii - 2 in roman numerals; an affirmative reply in Arabic, Hausa, Inuktitut, and Kikuyu
II - 2 in roman numerals
il - 49 in roman numerals
Il - the chemical symbol for Ilinium, an obsolete name for Promethium; the chemical symbol for Ilmenium, an obsolete name for Niobium or Samarium
IL - a symbol for idle, an indication that the computer is to wait; the postal abbreviation for Illinois; 49 in roman numerals
im - intramuscular, meaning through the muscles; 999 in roman numerals
IM - 999 in roman numerals
in - an inch, one twelfth of a foot
In - the chemical symbol for Indium; intortus, a variety of cloud which is entangled
In. - an abbreviation for Inuit
IN - the postal abbreviation for Indiana
io - an affirmative reply in Boloki, Fijian, and Mae
'io - an affirmative reply in Tongan
i-o - an affirmative reply in Pappua
Io - the chemical system for Ionium, an obsolete name for an isotope of Thorium
I/O - a computer symbol for input and output
IP - internet protocol, an online behavior system
i.q. - Latin idem quod => the same as
IQ - an abbreviation for intelligence quotient, a numerical measure of intelligence
Ir - the chemical symbol for Iridium; in the Bible, one of the descendants of Benjamin
Ir. - an abbreviation for Irish
IR - infrared light
Is - an abbreviation for Islands; an abbreviation for the Book of Isaiah
Is. - an abbreviation for the Book of Isaiah
-it - in Scottish, a suffix similar to the English '-ed'
It. - an abbreviation for Italian
IU - the international unit, a unit of the effect of vitamins and drugs
iv - intravenous, meaning through the veins; 4 in roman numerals
IV - intravenous, meaning through the veins; 4 in roman numerals
ix - 9 in roman numerals
IX - 9 in roman numerals

J

ja - an affirmative reply in Afrikaans, Alsacian, Coahuilteco, Danish, Dutch, Faroese, Frisian, German, Latvian, Low Saxon, Norwegian, old Prussian, Slovenian, Swedish, and Vöru
jå - an affirmative reply in German and Swabian
já - an affirmative reply in Icelandic
jâ - an affirmative reply in Sudovian
jä - an affirmative reply in Mazahua
JD - the Julian day, a part of a calendar system based on a 7980-year period; an abbreviation for a Dinar, a unit of currency
J.D. - Latin juris doctor => doctor of law
Jg - the chemical symbol for Jargonium, an obsolete name for Hafnium
ji - an affirmative reply in Bengali
J/K - an abbreviation for Joules per Kelvin, the unit of entropy
Jn - an abbreviation for the Gospel of John
Jn. - an abbreviation for the Gospel of John
jo - a Japanese unit of area for measuring the size of rooms in houses and apartments; an affirmative reply in Cassubian, Czech, Danish, Javanese, Luxemburgish, Mam, Norwegian, Palatinian, Platdeutsch, Pocomchi, and Swedish
jo - an affirmative reply in Popoluca
Jo - the chemical symbol for Joliotium, an obsolete name for Dubnium
Jr. - an abbreviation for Junior
ju - an affirmative reply in Nepali
Jy - jansky, a unit of flux

K

ka - an affirmative reply in Muskogee, Paamese, and Veps
ká - an affirmative reply in Creek
kA - a kiloamprere, which is 10^3 amperes
kb - a kilobar, a large metric unit of pressure; the kilobase, a unit of genetic information; a kilobit, 2^10 bits or 2^7 bytes
kB - a kilobyte, or 2^10 bytes
Kb - a kilobit, 2^10 bits or 2^7 bytes
KB - a kilobyte, or 2^10 bytes
kc - a kilocycle, which is 1000 cycles, or an informal name for the kilohertz (kHz)
kC - a kilocoulomb, which is 10^3 coulombs
KD - an abbreviation for a Dinar, a unit of currency
kF - a kilofarad, which is 10^3 farads
kg - a kilogram, which is 10^3 grams
Ki- - the prefix for kibi, which means 2^10 of
KI - potassium iodide
kJ - a kilojoule, which is 10^3 joules
kK - a kilokelvin, which is 10^3 kelvins
kl - a kiloliter, which is 10^3 liters
kL - a kiloliter, which is 10^3 liters
km - a kilometer, which is 10^3 meters
kM- - kilomega-, an obsolete prefix meaning 10^9 of
kn - a knot, a unit of speed equal to one nautical mile per hour
kN - a kilonewton, which is 10^3 newtons
Ko - a Thai word for 'island'
kp - the kilopond, a name for the kilogram of force which is a unit of force
Kr - the chemical symbol for Krypton; the abbreviation for a krona, a unit of currency
ks - a kilosecond, which is 10^3 seconds
KS - the postal abbreviation for Kansas
kt - a kiloton or kilotonne, which is 1000 kilotons or kilotonnes; a knot, a unit of speed equal to one nautical mile per hour
Ku - the chemical symbol for Kurchatovium, a suggested name for Rutherfordium
kV - a kilovolt, which is 10^3 volts
kw - a kilowatt, which is 10^3 watts
kW - a kilowatt, which is 10^3 watts
Ky - Nguyen Cao Ky, an ex-president of South Vietnam born in 1930
KY - the postal abbreviation for Kentucky

L

la - an affirmative reply in Yucatec Maya
la' - an affirmative reply in Lacandon
La - a lambert, which is a unit of luminence; the chemical symbol for Lanthanum; lacunosus, a variety of cloud that looks like a woven net
LA - the postal abbreviation for Louisiana
lb - pound, a unit of weight; the libra or libbra, a Spanish, Portuguese, or Italian unit of weight a little bigger than a pound
Lb - a lambert, which is a unit of luminence
L.B. - Latin literarum baccalaureus => bachelor of letters
lc. - a typographical symbol for lowercase
LC - a symbol for lower case, a typographical symbol to designate switching to lowercase letters; the Library of Congress
ld - 450 in roman numerals
LD - lunar distance, the average distance between the Earth and the Moon; lethal dose, the dose of a drug that will kill a certain percentage of a population; an abbreviation for a Dinar, a unit of currency; 450 in roman numerals
Le - the abbreviation for the leone, a unit of currency; the Lewis number, a calculation used in thermodynamic calculations
lf - linear foot, a one-foot length of a narrow object
lf. - a typographical symbol for light face, the opposite of bold face
LF - a symbol for the line feed, which moves the page down a line; low frequency radio (from 3-535 kHz) used for maritime communication
lg - length, a unit of distance
li - a Chinese unit of length; a line, a unit of distance; 51 in roman numerals
Li - the chemical symbol for Lithium
LI - 51 in roman numerals
Lk - an abbreviation for the Gospel of Luke
Lk. - an abbreviation for the Gospel of Luke
ll - a letter of the alphabet in Spanish
LL - an abbreviation for the pound, a unit of currency
lm - lumen, a unit of luminous flux; 950 in roman numerals
l/m - lines per minute, a unit of monitor picture reload speed
LM - 950 in roman numerals
l_P - (also l_P) the Planck length, which is the shortest possible length
Lr - the chemical symbol for Lawrencium
l/s - lines per second, a unit of monitor picture reload speed
L/s - liters per second, a unit of drainage speed
LS - an abbreviation for the pound, a unit of currency
L.S. - Latin locus sigilli => the place of the seal
Lt. - a military abbreviation for Lieutenant
Lu - the chemical symbol for Lutetium
lv - 55 in roman numerals
Lv - the symbol for the lev, a unit of currency
LV - 55 in roman numerals
Lw - an obsolete chemical symbol for Lawrencium
lx - lux, a unit of illuminence; 60 in roman numerals
LX - 60 in roman numerals
ly - a light year, the distance light travels in one year in a vacuum
Ly - a langley, a unit of heat transmission

M

ma - a Scottish word for 'my'
mA - a milliamprere, which is 10^-3 of an ampere
Ma - one million years; a mach, a unit of speed equal to the speed of sound; a megayear, a unit of time equal to one million years; the chemical symbol for Masurium, an obsolete name for Technetium
MA - a megamprere, which is 10^6 amperes; the postal abbreviation for Massachusetts; Latin magister artium => master of arts
mb - millibar, a unit of atmospheric pressure
Mb - a megabarrel, which is 10^6 barrels of oil; a megabase, a unit of genetic information of a million base pairs
MB - a megabyte, or 2^20 bytes; the postal abbreviation for Manitoba; Latin medicinæ baccalaureus => bachelor of medicine, an honorary title
mc - an alternate symbol for micro-, meaning one thousandth of; a micron, a millionth of a meter; Italian metro cubo => cubic meter; a millihertz, a thousandth of a hertz; 1100 in roman numerals
mc- - an alternate symbol for micro-, meaning one thousandth of
mC - a millicoulomb, which is 10^-3 of a coulomb
Mc - a megacycle, one million cycles or a megahertz
MC - a megacoulomb, which is 10^6 coulombs; 1100 in roman numerals; an abbreviation for Member of Congress, an honorary title; master of ceremonies
md - a millidarcy, a measurement of permeability; 1500 in roman numerals
m_d - (also m_d) the mass of a deuteron, an isotope of Hydrogen
mD - a millidarcy, a measurement of permeability
Md - the chemical symbol for Mendelevium
MD - the postal abbreviation for Maryland; 1500 in roman numerals; Latin medicinæ doctor => doctor of medicine
mè - an affirmative reply in Sgaw Karen
m_e - (also m_e) the mass of an electron, a negatively charged particle
ME - the postal abbreviation for Maine
mf - Italian mezzoforte => medium-loud
mF - a millifarad, which is 10^-3 of a farad
MF - a megafarad, which is 10^6 farads; medium frequency radio (535-1605 kHz) used for AM radio; an abbreviation for microfiche, a way of storing large documents in a small space
mg - a milligram, which is 10^-3 of a gram
mG - a milligauss, a unit of magnetic flux density equal to a thousandth of a gauss
Mg - a megagram, which is 10^6 grams; the chemical symbol for Magnesium
MG - an abbreviation for a Major General, an army rank
mH - a millihenry, a unit of electric inductance
MH - the postal abbreviation for the Marshall Islands
mi - a mile, which is 5280 feet; 1001 in roman numerals; an affirmative reply in Tay
Mi- - the prefix for mebi, which means 2^20 of
MI - the postal abbreviation for Michigan; 1001 in roman numerals
mJ - a millijoule, which is 10^-3 of a joule
MJ - a megajoule, which is 10^6 joules
mK - a millikelvin, which is 10^-3 of a kelvin
Mk - an abbreviation for the Gospel of Mark
Mk. - an abbreviation for the Gospel of Mark
MK - a megakelvin, which is 10^6 kelvins; the symbol for a markka, a unit of currency
ml - a milliliter, which is 10^-3 of a liter; 1050 in roman numerals
mL - a milliliter, which is 10^-3 of a liter
Ml - a megaliter, which is 10^6 liters
ML - a megaliter, which is 10^6 liters; 1050 in roman numerals
mm - a millimeter, which is 10^-3 of a meter; 2000 in roman numerals; an affirmative reply in Dschang, Sango, and Telefol
m/m - by mass, a way to measure the concentration of something
m.m. - Latin mutatis mutandis => with the necessary changes
Mm - a megameter, which is 10^6 meters
MM - an old abbreviation for one million; 2000 in roman numerals
MM. - an abbreviation for messieurs, the plural of Mister or Monsieur
m_n - (also m_n) the mass of a neutron, an uncharged particle
m.n. - Latin mutato nomine => with the name being changed
mN - a millinewton, which is 10^-3 of a newton
Mn - the chemical symbol for Manganese
MN - a meganewton, which is 10^6 newtons; the postal abbreviation for Minnesota
mo - month, a unit of time
-mo - a printing suffix used to describe the cut page size of a book
Mo - the chemical symbol for Molybdenum
MO - the postal abbreviation for Missouri
mp - melting point, the temperature at which a substance turns from liquid to solid or vice versa; Italian mezzopiano => medium-quiet
m_p - (also m_p) the mass of a proton, a positively charged particle
mP - a micropoise, a unit of dynamic viscosity
m_P - (also m_P) the Planck mass, which is the smallest possible mass something can have
Mp - a megapond, an archaic metric unit of force
MP - an abbreviation for Military Police; the postal abbreviation for the Northern Mariana Islands; a Member of Parliament, a British position approximately equivalent to Senator in the US
M.P. - an abbreviation for Member of Parliament
mq - Italian metro quadrato => square meter
mr - the milliroentgen, a quantity of radiation
Mr. - an abbreviation for Mister, a title signifying a man
ms - a millisecond, which is 10^-3 of a second
mS - a millisiemens, a unit of conductance
Ms - a megasecond, which is 10^6 seconds; the chemical symbol for Masrium, an obsolete name for Indium
Ms. - an abbreviation for Miss, a title signifying an unmarried woman
MS - the postal abbreviation for Mississippi
MS. - Latin manuscriptum => manuscript
M.S. - an abbreviation for Master of Science
m.t. - an abbreviation for the mountain time zone
mT - a millitesla, a unit of magnetic field intensity
Mt - a megaton, a unit of the energy in an explosion; a megatonne, a metric unit of mass equal to the teragram, which is 10^12 grams; the chemical symbol for Meitnerium; an abbreviation for the Gospel of Matthew
Mt. - an abbreviation for Mount, as in Mt. Vesuvius; an abbreviation for the Gospel of Matthew
MT - measurement ton, a unit of volume equal to 40 cubic feet; a metric tonne, equal to a million grams; the postal abbreviation for Montana
mu - a millimass unit, equal to a thousandth of an atomic mass unit; a Chinese unit of land area
MU - a mouse unit, defined as the dose of a toxin that will kill 50% of all mice
mv - 1005 in roman numerals
mV - a millivolt, which is 10^-3 of a volt
Mv - an obsolete chemical symbol for Mendelevium
MV - a megavolt, which is 10^6 volts; 1005 in roman numerals
mW - a milliwatt, which is 10^-3 of a watt
MW - a megawatt, which is 10^6 watts
mx - 1010 in roman numerals
Mx - maxwell, a unit of magnetic flux
MX - 1010 in roman numerals
my- - a prefix for the obsolete myria-, meaning ten thousand of

N

na - an affirmative reply in Besisi
nä - an affirmative reply in Livonian
-na - in Scottish, a verb suffix that makes the verb negative
nA - a nanoamprere, which is 10^-9 of an ampere
Na - the chemical symbol for Sodium
NA - the numberical aperture, the size of the cone of light pertaining to some optical equipment; an abbreviation for not available; not applicable
N/A - an abbreviation for not available
N_A - (also N_A) Avogadro's number, the number of atoms in a mole, which is 6.022 x 10^23
N.A. - the numberical aperture, the size of the cone of light pertaining to some optical equipment
nb - a nanobar, a small unit of pressure
Nb - the chemical symbol for Niobium
NB - the postal abbreviation for New Brunswick
N.B. - Latin nota bene => note well
nC - a nanocoulomb, which is 10^-9 of a coulomb
NC - the noise criterion, an engineering unit to measure if sound levels are acceptable; the postal abbreviation for North Carolina
Nd - the chemical symbol for Neodymium
ND - the postal abbreviation for North Dakota
ne - an affirmative reply in Greek and Korean
né - an affirmative reply in ancient Greek
Ne - the chemical symbol for Neon; the neper, a unit used to express ratios logarithmically
NE - the niacin equivalent, a unit in nutrition; northeast, a direction equally northward and eastward; the postal abbreviation for Nebraska
NE. - an abbreviation for northeast
nF - a nanofarad, which is 10^-9 of a farad
NF - the postal abbreviation for Newfoundland and Labrador
N.F. - an abbreviation for National Formulary
ng - a nanogram, which is 10^-9 of a gram
Ng - the chemical symbol for Norwegium, an obsolete name for Hafnium; Ng Poon Chew, a clergyman living 1866-1931
NH - the postal abbreviation for New Hampshire
Ni - the chemical symbol for Nickel; the chemical symbol for Niton, an obsolete name for Radon
nJ - a nanojoule, which is 10^-9 of a joule
NJ - the postal abbreviation for New Jersey
nk - a unit of distance in horse racing
nK - a nanokelvin, which is 10^-9 of a kelvin
nl - a nanoliter, which is 10^-9 of a liter
n.l. - Latin non licet => it is not permitted; Latin non liquet => it is not clear; Latin non longe => not far; an abbreviation for the natural logarithm, a lograrithm to base e
nL - a nanoliter, which is 10^-9 of a liter
Nl - the normal liter, a unit of gas mass at standard temperature and pressure
NL - the normal liter, a unit of gas mass at standard temperature and pressure; a symbol for new line, a printing technique which goes to the next line; the postal abbreviation for the Netherlands
nm - a nanometer, which is 10^-9 of a meter
Nm - the newton-meter, a unit of torque; normal metric, a unit of worsted yarn density
NM - a nautical mile, about 6080 feet; the postal abbreviation for New Mexico
n'n - an affirmative reply in Koiari
nN - a nanonewton, which is 10^-9 of a newton
no - in Scottish, the word for 'not'; in English, a negative reply; an affirmative reply in Komi-Permyak
-no - in Latin, a suffix denoting a question
No - the chemical symbol for Nobelium; the chemical symbol for Norium, an obsolete name for Hafnium
No. - a literary abbreviation for number
NO - nitrogen monoxide
Np - a neper, a logarithmic ratio; the chemical symbol for Neptunium
NP - a symbol for new page, which skips to another page and continues printing on that new page
NR - the noise rating, an engineering unit to measure if sound levels are acceptable
ns - a nanosecond, which is 10^-9 of a second
Ns - the chemical symbol for Neilsbohrium, a suggested name for Dubnium or Bohrium; nimbostratus, a dark cloud that produces precipitation
NS - new style, a dating notation used to indicate a date is part of the Gregorian calendar rather than the Julian; the postal abbreviation for Nova Scotia; an abbreviatino for a nuclear ship
nt - a nit, a unit of luminence
nT - a nanotesla, a unit of magnetic field strength equal to 10^-9 of a tesla
NT - a net ton, used for either 2000 pounds or 100 cubic feet; the New Testament of the Bible (the Gospels, the letters, and Revelation); the postal abbreviation for the Northwest Territories, of Canada
nu - a measure of the dispersiveness of a lens or a prism; an affirmative reply in Russian
Nu - the name of a certain Burmese statesman
nV - a nanovolt, which is 10^-9 of a volt
NV - the postal abbreviation for Nevada
nW - a nanowatt, which is 10^-9 of a watt
Nw - normal worsted, a unit of worsted yarn density
NW - northwest, a direction equally north and west
NW. - an abbreviation for northwest
Ny - the chemical symbol for Neoytterbium, an obsolete name for Ytterbium
NY - the postal abbreviation for New York
NZ - an abbreviation for New Zealand

O

ob. - Latin obiit => he or she died; Latin obiter => incidentally
Ob - the Ob valley
oc - an affirmative reply in Gascon
òc - an affirmative reply in Provencal
o.c. - Latin opere citato => in the work cited
od - an abbreviation for outside diameter
OD - optical density, a measurement of the amount of light that can get through something; officer of the day; an overdose (on drugs)
O.D. - an abbreviation for a doctor of optometry
oé - an affirmative reply in Ewondo
o'e - an affirmative reply in Koiari
Oe - oersted, a unit of magnetic field strength
Og - in the Book of Numbers, the king of Bashan
öh - an affirmative reply in Stieng
OH - the postal abbreviation for Ohio
-OH - hydroxyl group
oi - an affirmative reply in Konkani and Loglan
oí - an affirmative reply in Provencal
ok - an affirmative reply in Mam
OK - the postal abbreviation for Oklahoma; an American affirmative
'om - an affirmative reply in Kamviri
OM - a symbol for the osmark, a unit of currency
On - in the Book of Numbers, one of the leaders of the rebellion of Korah
on - an affirmative reply in Osage
ON - the postal abbreviation for Ontario
oo - an affirmative reply in Auca, Dagaare, Hokkien, and Visayan
óo - an affirmative reply in Tagalog
op. - Latin opus => work; Latin opera => works
Op - opacus, a variety of cloud that lets absolutely no light through
OR - the postal abbreviation for Oregon
Os - the chemical symbol for Osmium
OS - old style, a dating notation used to express that a date is in the Julian calendar as opposed to in the Gregorian
OT - the Old Testament of the Bible (the Torah / the Books of Moses, the Writings, the Prophets)
ou - an affirmative reply in Nukuoro and Semang
'o'u - an affirmative reply in Kamviri
ow - an affirmative reply in Amharic
ox - an affirmative reply in Mien; a strong hooved animal
Ox - in the apocryphal Book of Judith, 8:1, the grandfather of Judith
-oy - a Faroese suffix meaning 'island'
-øy - a Norwegian suffix meaning 'island'
oz - ounce, a sixteenth of a pound; an ounce of force, a unit of force; an affirmative reply in Mien

P

pa - an affirmative reply in Gerung
p.a. - Latin per annum => every year; Latin pro anno => for the year
pA - a picoamprere, which is 10^-12 of an ampere
Pa - pascal, which is a unit of pressure; the chemical symbol for Protactinium; the chemical symbol for Protoactinium, an obsolete name for an isotope of Protactinium
PA - a petamprere, which is 10^15 amperes; per annum, a unit of frequency equal to once a year; the postal abbreviation for Pennsylvania; a public address system
Pb - the chemical symbol for Lead
pc - a parsec, a unit of distance equal to about 3.26 light years; a piece, a unit of quantity equal to 1
pC - a picocoulomb, which is 10^-12 of a coulomb
PC - a petacoulomb, which is 10^15 coulombs; a personal computer, a small computer designed for personal use
Pd - the chemical symbol for Palladium
PD - per diem, a unit of frequency equal to once a day; prism diopter, an optical unit of light deflection by a prism; the potential difference, or voltage, between two places on an electric circuit
pé - a Portuguese unit of length
Pe - the chemical symbol for Pelopium, an obsolete name for Niobium; perlucidus, a variety of cloud that lets sunlight through in certain places
PE - the postal abbreviation for Prince Edward Island
pf - power factor, a measure of the efficiency of a circuit
pF - a picofarad, which is 10^-12 of a farad; an obsolete agricultural unit of soil moisture tension; a puff, an informal name for a picofarad
PF - a petafarad, which is 10^15 farads; a symbol for punch off, an indication to stop punching text
pg - a picogram, which is 10^-12 of a gram
Pg - a petagram, which is 10^15 grams
ph - phot, a unit of illumination; a phase
pH - potential of Hydrogen, a logarithmic measure of the acidity or alkalinity of a solution based on the concentration of hyrdrogen ions
Ph - phenyl, a chemical
pi - (also π) the quotient between the circumference of a circle and the diameter of the same circle, equal to approximately 3.14159; a pica, a unit of length used by typographers
Pi- - a prefix for pebi, which means 2^50 of; a Chinese geographical word meaning 'point'
pJ - a picojoule, which is 10^-12 of a joule
PJ - a petajoule, which is 10^15 joules
pk - peck, one quarter of a bushel; pack, a commercial unit of quantity
pK - a picokelvin, which is 10^-12 of a kelvin
PK - a petakelvin, which is 10^15 kelvins
pl - a picoliter, which is 10^-12 of a liter; a poundal, an English unit of force
pl. - a literary abbreviation for plate (a page in color used for pictures)
pL - a picoliter, which is 10^-12 of a liter
Pl - a petaliter, which is 10^15 liters; a poiseuille, a unit of dynamic viscosity
Pl. - an abbreviation for Place, used in addresses
PL - a petaliter, which is 10^15 liters
pm - a picometer, which is 10^-12 of a meter; Latin post meridiem => after the meridian (after noon)
p.m. - Latin post meridiem => after noon
Pm - a petameter, which is 10^15 meters; the chemical symbol for Promethium
PM - Latin post meridiem => after the meridian (after noon); a permanent magnet; a symbol for the privacy message, a control character in ASCII
P.M. - Latin post mortem => after death
pN - a piconewton, which is 10^-12 of a newton
PN - a petanewton, which is 10^15 newtons; nominal pressure, the amount of pressure a valve, fitting, or pipe can withstand; a symbol for punch on, an indication to start punching text
po - an affirmative reply in Albanian
Po - poise, a unit of dynamic viscosity; the chemical symbol for Polonium
P.O. - the post office
pp - Italian pianissimo => very quiet
pp. - a literary abbreviation for pages
Pp - the chemical symbol for Phillipium, an obsolete name for Samarium or Holmium
PQ - an old postal abbreviation for Quebec
pr - pair, a unit of quantity equal to two
Pr - the chemical symbol for Praseodymium
PR - the postal abbreviation for Puerto Rico
ps - a picosecond, which is 10^-12 of a second; German pferdestärke, the word for horsepower
Ps - a petasecond, which is 10^15 seconds; the Book of Psalms; poise, a unit of synamic viscosity
Ps. - the Book of Psalms
PS - Latin post scriptum => after writing
P.S. - Latin post scriptum => after writing; public school
pt - pint, one eighth of a gallon; a point, a unit of typographical length
pt. - a literary abbreviation for part
pT - a picotesla, a unit of magnetic field strength which is 10^-12 of a tesla
Pt - the chemical symbol for Platinum
P.t. - an abbreviation for the pacific time zone
pu - a Chinese unit of distance
Pu - the chemical symbol for Plutonium
pV - a picovolt, which is 10^-12 of a volt
PV - a petavolt, which is 10^15 volts
pW - a picowatt, which is 10^-12 of a watt
PW - a petawatt, which is 10^15 watts; the postal abbreviation for Palau
PX - an abbreviation for post exchange
pz - pieze, a unit of pressure

Q

Qā' - an Arabic word meaning 'depression' in its geographical sense
QC - a postal abbreviation for Quebec
q.d. - Latin quaque die => once a day; Latin quasi dicat => as if one should say; Latin quasi dictum => as if said; Latin quasi dixisset => as if he had said
q.e. - Latin quod est => which is
q.h. - Latin quaque hora => each hour
q.l. - Latin quantum libet => as much as you please
qr - a quire, a unit of paper quantity
Qr - a quarter, a unit of weight
QR - a quarter, a unit of time equal to a quarter of a calendar year, a work year, or a school year
q.s. - Latin quantum sufficit => as much as is needed
qt - quart, one quarter of a gallon
QT - an abbreviation for 'on the quiet'
q.v. - Latin quod vide => which see; Latin quantum vis => as much as you will

R

Ra - the chemical symbol for Radium; radiatus, a variety of cloud that looks beamlike
rd - a rod, which is five and a half yards; a rad, a unit of radiation dose; a rare symbol for the rutherford, a unit of radioactivity
Rd - the rutherford, a unit of radioactivity
Rd. - an abbreviation for Road, used in addresses
Re - the chemical symbol for Rhenium; an old symbol for the rupee, a unit of currency
RE - retinol equivalent, a unit of vitamin A dosage
rf - radio frequency, the range of frequencies of radio waves that are used for radios
Rf - the chemical symbol for Rutherfordium
RF - an abbreviation for radiofrequency, a frequency in the accepted range of radio waves
Rh - the chemical symbol for Rhodium; a blood protein found in Rhesus monkeys
RH- - Rockwell hardness, a measure of metal hardness
ri - a Japanese unit of distance
RI - an abbreviation for the riyal, a unit of currency; a symbol for the reverse index, an indicator that the text is to be reversed; the postal abbreviation for Rhode Island
rm - a ream, a quantity of 500 sheets of paper
Rn - the chemical symbol for Radium Emanation, an obsolete name for Radon; the chemical symbol for Radon
Rp - the symbol for the rupiah, a unit of currency
rr - a letter of the alphabet in Spanish
rr. - Latin rarissime => very rarely
RR. - an abbreviation for railroad
r/s - revolutions per second, a unit of angular speed
Rs - a symbol for the rupee, a unit of currency
RS - a symbol for the record separator, a control character used to separate records in a database; a symbol for reader stop, an indication that the computer should stop reading the text
rT - a ton, a unit of cargo capacity
RT - a register ton, a unit of capacity equal to 100 cubic feet; revenue ton, a unit used for shipping billing; a ton, a unit of refrigeration power
Ru - the chemical symbol for Ruthenium
ry - a rydberg, a characteristic wave number of a certain frequency
Ry. - a railway

S

s.a. - Latin sine anno => without date; Latin secundum artem -> according to art
Sa - an obsolete chemical symbol for Samarium
sb - stilb, a unit of luminance
Sb - the chemical symbol for Antimony
sc. - Latin scire licet => that is to say; Latin sculpsit => he or she engraved it
s.c. - a typographical abbreviation for small caps
Sc - the chemical symbol for Scandium; stratocumulus, a low sheet of clouds
SC - the postal abbreviation for South Carolina
sd - the standard deviation, a statistical unit of data dispersion
s.d. - Latin sine die => without date, indefinately
SD - the postal abbreviation for South Dakota
S.D. - Latin salutem dicit => sends greetings
se - a Japanese unit of land area
Se - the chemical symbol for Selenium
SE - southeast, a direction equally southward and eastward
SE. - an abbreviation for southeast
sf - Italian sforzando => suddenly loud
Sf - an alternate abbreviation for a guilder, an obsolete Dutch form of currency; the sexagesimoquarto, a paper size
SF - the square foot; an abbreviation for the franc, a unit of currency
Sg - the chemical symbol for Seaborgium
Sh - the shannon, a unit of information content
si - an affirmative reply in Asturian, Catalan, Corsican, French, Galician, Hokkien, Interlingua, Papiamentu, Sicilian, and Valencian
sì - an affirmative reply in Friulian and Italian
sí - an affirmative reply in Malorquin and Spanish
Si - the chemical symbol for Silicon
SI - shift in, a printing device to enter into an alternate character set; French Système International d'unités, an association that sets standard values for units of measurement
SK - the postal abbreviation for Saskatchewan
Sm - the chemical symbol for Samarium
SM - set mode, an indication that the instructions are going to set the kind of typing
sn - the sthene, a metric unit of force
s.n. - Latin sine nomine => without name
Sn - the chemical symbol for Tin
So - an obsolete chemical symbol for Sodium; in the Second Book of Kings, 17:4, the king of Egypt
SO - shift out, a printing device to return from an alternate character set
sp - specific, used in front of certain measurements
s.p. - Latin sine prole => without issue
Sp. - an abbreviation for Spanish
SP - a symbol for the space; the shore patrol
sq - the square, a unit of area equal to 100 square feet
Sq. - an abbreviation for Square, used in addresses
sr - steradian, which is a unit of circular angle
Sr - the chemical symbol for Strontium
Sr. - an abbreviation for Senior
ss - an abbreviation for one half; Latin scilicet => namely (only used in law)
SS - a steamship
SS. - an abbreviation for Saints
st - stere, which is a cubic meter; a short ton, a weight of 2000 pounds
St - a stokes, which is a unit of viscosity; a stone, a British unit of weight of 14 pounds; the Stefan number, a measurement used in thermodynamics; stratus, a low featureless cloud type
St. - an abbreviation for Saint, as in St. John; an abbreviation for Street, used in addresses
ST - a symbol for the string terminator, a character signifying the end of a string
SU - the strontium unit, a unit of radioactive concentration
s.v. - Latin sub vode => under the word (to refer to reference works found below)
Sv - sievert, a unit of absorbed radiation dose
SW - a switch, an electronic unit used to open or close a circuit at will; southwest, a direction equally southward and westward
SW. - an abbreviation for southwest

T

Ta - the chemical symbol for Tantalum
TA - a teramprere, which is 10^12 amperes
Tb - the chemical symbol for Terbium
TB - a terabyte, which is 2^40 bytes; tuberculosis, a dangerous disease
Tc - the chemical symbol for Technetium; the abbreviation for the Tical, a unit of currency
TC - a teracoulomb, which is 10^12 coulombs
Td - the troland, a photometric unit for amount of light reaching the eye
TD - a transmitter-distributor, an archaic mechanical object used, for example, in typewriters
T.D. - an abbreviation for the Treasury Decisions
tê - an affirmative reply in Nganasan
Te - the chemical symbol for Tellurium; a musical abbreviation for the taille, a tenor oboe
TF - a terafarad, which is 10^12 farads
Tg - a teragram, which is 10^12 grams
th - a thermie, a unit of heat energy
Th - the chemical symbol for Thorium
Th. - an abbreviation for Thai
ti - an affirmative reply in Solresol, Tojolabal, and Tupi
Ti - the chemical symbol for Titanium
Ti- - a prefix for tebi-, which means 2^40 of
TJ - a terajoule, which is 10^12 joules
Tk - the abbreviation for the taka, a unit of currency
TK - a terakelvin, which is 10^12 kelvins
Tl - a teraliter, which is 10^12 liters; the chemical symbol for Thallium
TL - a teraliter, which is 10^12 liters; the abbreviation for the Turkish lira, a unit of currency
t.m. - the true mean, a statistical indicator
Tm - a terameter, which is 10^12 meters; the chemical symbol for Thulium
TM - a symbol for trademark; a symbol for tape mark, an indication to mark the information tape
tn - a ton, a weight unit of either two thousand pounds or a megagram; a short ton, a weight of 2000 pounds
Tn - the chemical symbol for Thoron, an obsolete name for Radon; an obsolete chemical symbol for Tungsten
TN - a teranewton, which is 10^12 newtons; the postal abbreviation for Tennessee
to - a Japanese unit of volume; an affirmative reply in Hmong
t_P - (also t_P) the Planck time, which is the smallest possible amount of time
tr - troy, a system of measuring
Tr - translucidus, a variety of cloud that lets sunlight through; a musical abbreviation for the trumpet
Ts - a terasecond, which is 10^12 seconds
Tt - the trigesimosecundo, a paper size
TT - the postal abbreviation for the Trust Territories of the Pacific
tu - a Chinese unit of distance
Tu - an obsolete chemical symbol for Thulium; an obsolete chemical symbol for Tungsten
TV - a teravolt, which is 10^12 volts; television
TW - a terawatt, which is 10^12 watts
TX - the postal abbreviation for Texas

U

ua - an alternate abbreviation for an Astonomical Unit, which is the average radius of Earth's orbit around the sun; an affirmative reply in Kapampangan
uc. - a typographical abbreviation for uppercase
UC - a symbol for upper case, a typographical method to type in upper case letters
UD - an abbreviation for a Dirham, a unit of currency
uF - erroneous symbol for microfarad, which is 10^-6 of a farad
UI - the international unit, a unit of drug activity
U I - the chemical symbol for Uranium I, an obsolete name for an isotope of Uranium
UM - an abbreviation for the ouguiya, a unit of currency
Un - undulatus, a variety of cloud that undulates around
UN - the United Nations, a European set of allies
U.N. - the United Nations, a European set of allies
Ur - in the Bible, the father of Eliphal
u.s. - Latin ubi supra => where mentioned above
US - the United States of America; a symbol for a unit separator, a control character used to separate information
U.S. - the United States Supreme Court Reports; the United States of America
UT - the universal time, the new name for Greenwich Mean Time; the postal abbreviation for Utah
uu - an affirmative reply in Gaam, Nukuoro, Shuri, and Telefol
üü - an affirmative reply in Ute
UV - ultraviolet light
ux. - Latin uxor => wife
UX - the siegbahn unit, a unit of length used in atomic spectroscopy
U Y - the chemical symbol for Uranium Y, an obsolete name for an isotope of Thorium
U Z - the chemical symbol for Uranium Z, an obsolete name for an isotope of Protactinium

V

va - an affirmative reply in Romani
VA - a volt-ampere, a unit of electric power equal to a watt; the postal abbreviation for Virginia
VB - Visual Basic, a programming language
vc - 95 in roman numerals
VC - 95 in roman numerals
vd - 495 in roman numerals
VD - a venereal desease, which is one that can be caught by genital contact; 495 in roman numerals
Ve - vertebratus, a variety of cloud that looks like bones of a fish
VF - the voice frequency, the range of frequencies human voice lies in, from 300 Hz to 3000 Hz
v.g. - Latin verbi gratia => for example
VG - the viscosity grade, a lubricant rating
vi - 6 in roman numerals
Vi - the chemical symbol for Virginium, an obsolete name for Francium
VI - the postal abbreviation for the Virgin Islands; 6 in roman numerals
vl - 45 in roman numerals
VL - 45 in roman numerals
vm - 995 in roman numerals
Vm - the chemical symbol for Virginium, an obsolete name for Francium
V/m - an abbreviation for volt per meter, a unit of electric field strength
VM - 995 in roman numerals
vs. - Latin versus => against
v.s. - Latin vide supra => see above
VT - a symbol for vertical tabulation, a method of lining up text; the postal abbreviation for Vermont
vu - the volume unit, a telecommunicatinos unit used to describe radio volume; the volumetric unit, a unit of volume
v.v. - Latin vice versa => the other way around
v/v - by volume, a unit of concentration

W

wa - an affirmative reply in Kala Kawaw Ya, Kaurareg, Mabuiag, and Yumpla Toc
WA - the postal abbreviation for Washington
Wb - weber, which is a unit of magnetic flux
WC - the water column, a pressure notation
wf - a typographical abbreviation for wrong font
Wh - a watt-hour, which is the power of a watt's energy being used for an hour
wi - an affirmative reply in Creole, Kreyol, and Seselwa
wi' - the Scottish word for 'with'
WI - the postal abbreviation for Wisconsin
wk - a week, which is seven days
WL - working level, a unit of radiation exposure
wm - an affirmative reply in Hmong
wo - an affirmative reply in Pashto
w/o - an abbreviation for without
WO - an abbreviation for Warrant Officer, an army rank
WS - German Wassersäule, used for measuring water pressure
Wu - Chien-Shiung Wu, a physicist born in 1912
w/v - an abbreviation for weight by volume
WV - the postal abbreviation for West Virginia
w/w - weight per weight, or weight concentration
wy - an affirmative reply in Magindano
WY - the postal abbreviation for Wyoming

X

xc - 90 in roman numerals
XC - 90 in roman numerals
xd - 490 in roman numerals
XD - 490 in roman numerals
Xe - the chemical symbol for Xenon
Xé - a Laotian word meaning 'river'
xi - 11 in roman numerals
XI - 11 in roman numerals
xl - 40 in roman numerals
XL - 40 in roman numerals; an abbreviation for extra large, a clothing size
xm - 990 in roman numerals
XM - 990 in roman numerals
XS - an abbreviation for extra small, a clothing size
Xu - the X unit, a tiny unit of distance
XU - the siegbahn unit, a unit of length used in atomic spectroscopy
xv - 15 in roman numerals
XV - 15 in roman numerals
xx - 20 in roman numerals
XX - a symbol for liquor of medium strength; in genetics, a normal woman (has two X chromosomes); 20 in roman numerals
XY - in genetics, a normal man (has an X chromosome and a Y chromosome)

Y

ya - one year ago; an affirmative reply in Breton, Bulu, Cornish, English, Indonesian, Khakas, Krio, Malay, Ndjuka, Sundanese, and Zapotec
ya' - an affirmative reply in Jakun
yA - a yoctoamprere, which is 10^-24 of an ampere
YA - a yottamprere, which is 10^24 amperes
Yb - the chemical symbol for Ytterbium
yC - a yoctocoulomb, which is 10^-24 of a coulomb
YC - a yottacoulomb, which is 10^24 coulombs
yd - a yard, which is three feet
ye - in Scottish, the word for 'you'; an affirmative reply in Korean and Yiddish
yé - an affirmative reply in Pa'ikwene
ye' - an affirmative reply in Washo
yF - a yoctofarad, which is 10^-24 of a farad
YF - a yottafarad, which is 10^24 farads
yg - a yoctogram, which is 10^-24 of a gram
Yg - a yottagram, which is 10^24 grams
yi - a Chinese unit of quantity equal to a hundred million
yJ - a yoctojoule, which is 10^-24 of a joule
YJ - a yottajoule, which is 10^24 joules
yK - a yoctokelvin, which is 10^-24 of a kelvin
YK - a yottakelvin, which is 10^24 kelvins
yl - a yoctoliter, which is 10^-24 of a liter
yL - a yoctoliter, which is 10^-24 of a liter
Yl - a yottaliter, which is 10^24 liters
YL - a yottaliter, which is 10^24 liters
ym - a yoctometer, which is 10^-24 of a meter
Ym - a yottameter, which is 10^24 meters
yN - a yoctonewton, which is 10^-24 of a newton
YN - a yottanewton, which is 10^24 newtons
yo - an affirmative reply in Gumatj, Kanuri, Tamashek, Yiddish, and Yolngu Matha
yò - an affirmative reply in Ngbaka
y/o - a symbol for years old
YR - a symbol for the rial, a unit of currency
ys - a yoctosecond, which is 10^-24 of a second
Ys - a yottasecond, which is 10^24 seconds
Yt - an obsolete chemical symbol for Yttrium
YT - the postal abbreviation for the Yukon Territory
yu - an affirmative reply in Dyirbal and Walmulla
Yü - a Chinese word meaning 'island'
yV - a yoctovolt, which is 10^-24 of a volt
YV - a yottavolt, which is 10^24 volts
yW - a yoctowatt, which is 10^-24 of a watt
YW - a yottawatt, which is 10^24 watts
yy - an affirmative reply in Nganasan

Z

zA - a zeptoamprere, which is 10^-21 of an ampere
ZA - a zettamprere, which is 10^21 amperes
zC - a zeptocoulomb, which is 10^-21 of a coulomb
ZC - a zettacoulomb, which is 10^21 coulombs
zF - a zeptofarad, which is 10^-21 of a farad
ZF - a zettafarad, which is 10^21 farads
zg - a zeptogram, which is 10^-21 of a gram
Zg - a zettagram, which is 10^21 grams
zJ - a zeptojoule, which is 10^-21 of a joule
ZJ - a zettajoule, which is 10^21 joules
zK - a zeptokelvin, which is 10^-21 of a kelvin
ZK - a zettakelvin, which is 10^21 kelvins
zl - a zeptoliter, which is 10^-21 of a liter
zL - a zeptoliter, which is 10^-21 of a liter
Zl - a zettaliter, which is 10^21 liters; an abbreviation for the zloty, a unit of currency
ZL - a zettaliter, which is 10^21 liters
zm - a zeptometer, which is 10^-21 of a meter
Zm - a zettameter, which is 10^21 meters
zN - a zeptonewton, which is 10^-21 of a newton
Zn - the chemical symbol for Zinc
ZN - a zettanewton, which is 10^21 newtons
Zr - the chemical symbol for Zirconium
zs - a zeptosecond, which is 10^-21 of a second
Zs - a zettasecond, which is 10^21 seconds
zV - a zeptovolt, which is 10^-21 of a volt
ZV - a zettavolt, which is 10^21 volts
zW - a zeptowatt, which is 10^-21 of a watt
ZW - a zettawatt, which is 10^21 watts

Online References

How Many: A Dictionary of Units of Measurement
The Frink file for non-changing units
Elementymology & Elements Multidict
ASCII-EBCDIC Chart
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Standard Latin Abbreviations $amp; Phrases
Abbreviations and Letter Symbols
Scottish Words
"Yes" in over 550 languages
Music Terms
Old Scottish Words in Use Today