Note: udunits.dat from unidata.ucar.edu  
http://www.unidata.ucar.edu/packages/udunits/udunits.dat

# $Id: udunits_1998.dat,v 1.1 2005/06/02 19:52:15 ansley Exp $
#
# The first column is the unit name.  The second column indicates whether or
# not the unit name has a plural form (i.e. with an 's' appended).  
# A 'P' indicates that the unit has a plural form, whereas, a 'S' indicates
# that the unit has a singular form only.  The remainder of the line is the 
# definition for the unit.
#
# '#' is the to-end-of-line comment-character.
#
# NB: When adding to this table, be *very* careful to distinquish between
# the letter 'O' and the numeral zero '0'.  For example, the following two
# entries don't do what one might otherwise expect:
#
#	mercury_0C		mercury_32F
#	millimeter_Hg_0C	mm mercury_OC

#
# BASE UNITS.  These must be first and are identified by a nil definition.
#
ampere			P			# electric current
count			P			# dimensionless decimal number
candela			P			# luminous intensity
kelvin			P			# thermodynamic temperature
kilogram		P			# mass
meter			P			# length
mole			P			# amount of substance
second			P			# time
radian			P			# plane angle

#
# CONSTANTS
#
percent			S 0.01
PI			S 3.14159265358979323846
bakersdozen		S 13
pair			P 2
ten			P 10
dozen			S 12
score			S 20
hundred			P 100
thousand		P 1.0e3
million			P 1.0e6

%			S percent
pi			S PI

#
# NB: All subsequent definitions must be given in terms of
# earlier definitions.  Forward referencing is not permitted.
#

#
# The following are non-base units of the fundamental quantities
#

bit			P count			# unit of information

#
# UNITS OF ELECTRIC CURRENT
#
A			S ampere
amp			P ampere
abampere		P 10 ampere		# exact
gilbert			P 7.957747e-1 ampere
statampere		P 3.335640e-10 ampere
biot			P 10 ampere

#
# UNITS OF LUMINOUS INTENSITY
#
cd			S candela
candle			P candela

#
# UNITS OF THERMODYNAMIC TEMPERATURE
#
degree_Kelvin		P kelvin
degree_Celsius		S kelvin @ 273.15
degree_Rankine		P kelvin/1.8
degree_Fahrenheit	P degree_Rankine @ 459.67

#C			S degree_Celsius	# `C' means `coulomb'
Celsius			S degree_Celsius
celsius			S degree_Celsius
degree_centigrade	S degree_Celsius	# approx. was just `centigrade'
degC			S degree_Celsius
degreeC			S degree_Celsius
degree_C		S degree_Celsius
degree_c		S degree_Celsius
deg_C			S degree_Celsius
deg_c			S degree_Celsius
degK			S kelvin
degreeK			S kelvin
degree_K		S kelvin
degree_k		S kelvin
deg_K			S kelvin
deg_k			S kelvin
K			S kelvin
Kelvin			P kelvin

degF			S degree_Fahrenheit
degreeF			S degree_Fahrenheit
degree_F		S degree_Fahrenheit
degree_f		S degree_Fahrenheit
deg_F			S degree_Fahrenheit
deg_f			S degree_Fahrenheit
F			S degree_Fahrenheit
Fahrenheit		P degree_Fahrenheit
fahrenheit		P degree_Fahrenheit

degR			S degree_Rankine
degreeR			S degree_Rankine
degree_R		S degree_Rankine
degree_r		S degree_Rankine
deg_R			S degree_Rankine
deg_r			S degree_Rankine
#R			S degree_Rankine	# `R' means `roentgen'
Rankine			P degree_Rankine
rankine			P degree_Rankine

#
# UNITS OF MASS
#
assay_ton		P 2.916667e-2 kilogram	# was 2.916667e2 (typo!)
avoirdupois_ounce	P 2.834952e-2 kilogram
avoirdupois_pound	P 4.5359237e-1 kilogram	# exact
carat			P 2e-4 kilogram
grain			P 6.479891e-5 kilogram	# exact
gram			P 1e-3 kilogram		# exact
kg			S kilogram
long_hundredweight	P 5.080235e1 kilogram
metric_ton		P 1e3 kilogram		# exact
pennyweight		P 1.555174e-3 kilogram
short_hundredweight	P 4.535924e1 kilogram
slug			P 14.59390 kilogram
troy_ounce		P 3.110348e-2 kilogram
troy_pound		P 3.732417e-1 kilogram
atomic_mass_unit	P 1.66054e-27 kilogram	# was 1.66044e-27

tonne			P metric_ton
apothecary_ounce	P troy_ounce
apothecary_pound	P avoirdupois_pound
pound			P avoirdupois_pound
metricton		P metric_ton
gr			S grain
scruple			P 20 grain
apdram			P 60 grain
apounce			P 480 grain
appound			P 5760 grain
atomicmassunit		P atomic_mass_unit
amu			P atomic_mass_unit

t			S tonne
lb			P pound
bag			P 94 pound
short_ton		P 2000 pound
long_ton		P 2240 pound

ton			P short_ton
shortton		P short_ton
longton			P long_ton

#
# UNITS OF LENGTH
#
angstrom		P decinanometer
astronomical_unit	P 1.495979e11 meter
fermi			P 1e-15 meter		# exact
m			S meter
metre			P meter
light_year		P 9.46073e15 meter	# was ASTM's 9.46055e15 meter
micron			P 1e-6 meter		# exact
mil			P 2.54e-5 meter		# exact
nautical_mile		P 1.852000e3 meter	# exact
parsec			P 3.085678e16 meter
printers_point		P 3.514598e-4 meter

# God help us!  There's an international foot and a US survey foot and
# they're not the same!

# US Survey foot stuff:
US_survey_foot		S (1200/3937) meter	# exact
US_survey_feet		S US_survey_foot	# alias
US_survey_yard		P 3 US_survey_feet	# exact
US_survey_mile		P 5280 US_survey_feet	# exact
US_statute_mile		P US_survey_mile	# alias
rod			P 16.5 US_survey_feet	# exact
pole			P rod			# alias
perch			S rod			# alias
perches			S perch			# alias
furlong			P 660 US_survey_feet	# exact
fathom			P 6 US_survey_feet	# exact

# International foot stuff:
international_inch	S 2.54 cm		# exact
international_inches	S international_inch	# alias
international_foot	S 12 international_inches	# exact
international_feet	S international_foot	# alias
international_yard	P 3 international_feet	# exact
international_mile	P 5280 international_feet	# exact

# Alias unspecified units to the international units:
inch			S international_inch	# alias
foot			S international_foot	# alias
yard			P international_yard	# alias
mile			P international_mile	# alias

# The following should hold regardless:
inches			S inch			# alias
in			S inches		# alias
feet			S foot			# alias
ft			S feet			# alias
yd			S yard			# alias

chain			P 2.011684e1 meter

printers_pica		P 12 printers_point	# exact
astronomicalunit	P astronomical_unit
au			S astronomical_unit
nmile			P nautical_mile
nmi			S nautical_mile

pica			P printers_pica
big_point		P inch/72		# exact
barleycorn		P inch/3

arpentlin		P 191.835 foot

#
# UNITS OF AMOUNT OF SUBSTANCE
#
mol			S mole

#
# UNITS OF TIME
#
day			P 8.64e4 second		# exact
hour			P 3.6e3 second		# exact
minute			P 60 second		# exact
s			S second
sec			P second
shake			P 1e-8 second		# exact
sidereal_day		P 8.616409e4 second
sidereal_hour		P 3.590170e3 second
sidereal_minute		P 5.983617e1 second
sidereal_second		P 0.9972696 second
sidereal_year		P 3.155815e7 second
# Interval between 2 successive passages of sun through vernal equinox
# (365.242198781 days -- see 
# http://www.ast.cam.ac.uk/pubinfo/leaflets/,
# http://aa.usno.navy.mil/AA/
# and http://adswww.colorado.edu/adswww/astro_coord.html):
tropical_year		P 3.15569259747e7 second
lunar_month		P 29.530589 day

common_year		P 365 day		# exact: 153600e7 seconds
leap_year		P 366 day		# exact
Julian_year		P 365.25 day		# exact
Gregorian_year		P 365.2425 day		# exact
sidereal_month		P 27.321661 day
tropical_month		P 27.321582 day
d			S day
min			P minute
hr			P hour
h			S hour
fortnight		P 14 day		# exact
week			P 7 day			# exact
jiffy			S 0.01 second		# believe it or not!
jiffies			S jiffy			# assumed plural spelling

year			P tropical_year

yr			P year
a			S year			# "anno"
eon			P 1e9 year		# fuzzy
month			P year/12		# on average

#
# UNITS OF PLANE ANGLE
#
#rad			P radian		# `rad' means `grey'
circle			P 2 pi radian
angular_degree		P (pi/180) radian

turn			P circle
degree			P angular_degree
degree_north		S angular_degree
degree_east		S angular_degree
degree_true		S angular_degree
arcdeg			P angular_degree
angular_minute		P angular_degree/60
angular_second		P angular_minute/60
grade			P 0.9 angular_degree	# exact

degrees_north		S degree_north
degreeN			S degree_north
degree_N		S degree_north
degreesN		S degree_north
degrees_N		S degree_north

degrees_east		S degree_east
degreeE			S degree_east
degree_E		S degree_east
degreesE		S degree_east
degrees_E		S degree_east

degree_west             S -1 degree_east
degrees_west            S degree_west
degreeW                 S degree_west
degree_W                S degree_west
degreesW                S degree_west
degrees_W               S degree_west

degrees_true		S degree_true
degreeT			S degree_true
degree_T		S degree_true
degreesT		S degree_true
degrees_T		S degree_true

arcminute		P angular_minute
arcsecond		P angular_second

arcmin			P arcminute
arcsec			P arcsecond

#
# The following are derived units with special names.  They are useful for
# defining other derived units.
#
steradian		P radian2
hertz			S 1/second
newton			P kilogram.meter/second2
coulomb			P ampere.second
lumen			P candela steradian
becquerel		P 1/second		# SI unit of activity of a 
#						# radionuclide
standard_free_fall	S 9.806650 meter/second2	# exact

pascal			P newton/meter2
joule			P newton.meter
hz			S hertz
sr			S steradian
force			S standard_free_fall
gravity			S standard_free_fall
free_fall		S standard_free_fall
lux			S lumen/meter2
sphere			P 4 pi steradian

luxes			S lux
watt			P joule/second
gray			P joule/kilogram	# absorbed dose. derived unit
sievert			P joule/kilogram	# dose equivalent. derived unit
conventional_mercury	S gravity 13595.10 kg/m3
mercury_0C		S gravity 13595.1 kg/m3	# was 13595.065
mercury_60F		S gravity 13556.8 kg/m3	# was 13556.806
conventional_water	S gravity 1000 kg/m3	# exact
water_4C		S gravity 999.972 kg/m3	# was 999.97226
water_60F		S gravity 999.001 kg/m3	# was 999.00072
g			S gravity		# approx. should be `local'

volt			P watt/ampere
mercury_32F		S mercury_0C
water_39F		S water_4C		# actually 39.2 F
mercury			S conventional_mercury	# was mercury_32F
water			S conventional_water	# was water_4C

farad			P coulomb/volt
ohm			P volt/ampere
siemens			S ampere/volt
weber			P volt.second
Hg			S mercury
hg			S mercury
H2O			S water
h2o			S water

tesla			P weber/meter2
henry			P weber/ampere

#
# The following are compound units: units whose definitions consist 
# of two or more base units.  They may now be defined in terms of the 
# preceding units.
#

#
# ACCELERATION
#
gal			P 1e-2 meter/second2	# exact

#
# Area
#
are			P 1e2 m2		# exact
barn			P 1e-28 m2		# exact
circular_mil		P 5.067075e-10 m2
darcy			P 9.869233e-13 m2	# permeability of porous solids
hectare			P 1e4 m2		# exact
acre			P 160 rod2		# exact

#
# ELECTRICITY AND MAGNETISM
#
abfarad			P 1e9 farad		# exact
abhenry			P 1e-9 henry		# exact
abmho			P 1e9 siemens		# exact
abohm			P 1e-9 ohm		# exact
abvolt			P 1e-8 volt		# exact
C			S coulomb
e			S 1.60217733-19 coulomb	# was 1.6021917e-19
chemical_faraday	P 9.64957e4 coulomb
physical_faraday	P 9.65219e4 coulomb
C12_faraday		P 9.648531e4 coulomb
gamma			P 1e-9 tesla		# exact
gauss			S 1e-4 tesla		# exact
H			S henry
maxwell			P 1e-8 weber		# exact
oersted			P 7.957747e1 ampere/meter
S			S siemens
statcoulomb		P 3.335640e-10 coulomb
statfarad		P 1.112650e-12 farad
stathenry		P 8.987554e11 henry
statmho			P 1.112650e-12 siemens
statohm			P 8.987554e11 ohm
statvolt		P 2.997925e2 volt
T			S tesla
unit_pole		P 1.256637e-7 weber
V			S volt
Wb			S weber
mho			P siemens
Oe			S oersted
faraday			P C12_faraday		# charge of 1 mole of 
#						# electrons

#
# ENERGY (INCLUDES WORK)
#
electronvolt		P 1.602177e-19 joule
erg			P 1e-7 joule		# exact
IT_Btu			P 1.05505585262e3 joule	# exact, was 1.055056e3
EC_therm		P 1.05506e8 joule	# exact
thermochemical_calorie	P 4.184000 joule	# exact
IT_calorie		P 4.1868 joule		# exact
J			S joule
ton_TNT			S 4.184e9 joule
US_therm		P 1.054804e8 joule	# exact
watthour		P watt hour

therm			P US_therm
Wh			S watthour
Btu			P IT_Btu
calorie			P IT_calorie
electron_volt		P electronvolt

thm			S therm
cal			S calorie
eV			S electronvolt
bev			S gigaelectron_volt

#
# FORCE
#
dyne			P 1e-5 newton		# exact
pond			P 9.806650e-3 newton	# exact, was 1.806650e-3 (typo)
force_kilogram		S 9.806650 newton	# exact
force_ounce		S 2.780139e-1 newton
force_pound		S 4.4482216152605 newton# exact
poundal			P 1.382550e-1 newton
N			S newton
gf			S gram force

force_gram		P 1e-3 force_kilogram
force_ton		P 2000 force_pound	# exact
lbf			S force_pound
ounce_force		S force_ounce
kilogram_force		S force_kilogram
pound_force		S force_pound
ozf			S force_ounce
kgf			S force_kilogram

kip			P 1000 lbf
ton_force		S force_ton
gram_force		S force_gram

#
# HEAT
#
clo			P 1.55e-1 kelvin.meter2/watt

#
# LIGHT
#
lm			S lumen
lx			S lux
footcandle		P 1.076391e-1 lux
footlambert		P 3.426259 candela/meter2
lambert			P (1e4/PI) candela/meter2	# exact
stilb			P 1e4 candela/meter2	# exact
phot			P 1e4 lumen/meter2	# exact
nit			P 1 candela/meter2	# exact
langley			P 4.184000e4 joule/meter2	# exact
blondel			P candela/(pi meter2)

apostilb		P blondel
nt			S nit
ph			S phot
sb			S stilb

#
# MASS PER UNIT LENGTH
#
denier			P 1.111111e-7 kilogram/meter
tex			P 1e-6 kilogram/meter	# exact

#
# MASS PER UNIT TIME (INCLUDES FLOW)
#
perm_0C			S 5.72135e-11 kg/(pascal second meter2)
perm_23C		S 5.74525e-11 kg/(pascal second meter2)

#
# POWER
#
voltampere		P volt ampere
VA			S volt ampere
boiler_horsepower	P 9.80950e3 watt
shaft_horsepower	P 7.456999e2 watt
metric_horsepower	P 7.35499 watt
electric_horsepower	P 7.460000e2 watt	# exact
W			S watt
water_horsepower	P 7.46043e2 watt
UK_horsepower		P 7.4570e2 watt
refrigeration_ton	P 12000 Btu/hour

horsepower		P shaft_horsepower
ton_of_refrigeration	P refrigeration_ton

hp			S horsepower

#
# PRESSURE OR STRESS
#
bar			P 1e5 pascal		# exact
standard_atmosphere	P 1.01325e5 pascal	# exact
technical_atmosphere	P 1 kg gravity/cm2	# exact
inch_H2O_39F		S inch water_39F
inch_H2O_60F		S inch water_60F
inch_Hg_32F		S inch mercury_32F
inch_Hg_60F		S inch mercury_60F
millimeter_Hg_0C	S mm mercury_0C
footH2O			S foot water
cmHg			S cm Hg
cmH2O			S cm water
Pa			S pascal
inch_Hg			S inch Hg
inch_hg			S inch Hg
inHg			S inch Hg
in_Hg			S inch Hg
in_hg			S inch Hg
millimeter_Hg		S mm Hg
mmHg			S mm Hg
mm_Hg			S mm Hg
mm_hg			S mm Hg
torr			P mm Hg
foot_H2O		S foot water
ftH2O			S foot water
psi			S 1 pound gravity/in2
ksi			S kip/in2
barie			P 0.1 newton/meter2

at			S technical_atmosphere
atmosphere		P standard_atmosphere
atm			P standard_atmosphere
barye			P barie

#
# RADIATION UNITS
#
Bq			S becquerel
curie			P 3.7e10 becquerel	# exact
rem			P 1e-2 sievert		# dose equivalent. exact
rad			P 1e-2 gray		# absorbed dose. exact
roentgen		P 2.58e-4 coulomb/kg	# exact
Sv			S sievert
Gy			S gray

Ci			S curie
R			S roentgen
rd			S rad

#
# VELOCITY (INCLUDES SPEED)
#
c			S 2.997925e+8 meter/sec
knot			P nautical_mile/hour

knot_international	S knot
international_knot	S knot
kt			P knot

#
# VISCOSITY
#
poise			S 1e-1 pascal second	# absolute viscosity. 
#						# exact
stokes			S 1e-4 meter2/second	# exact
rhe			S 10/(pascal second)	# exact

St			S stokes

#
# VOLUME (INCLUDES CAPACITY)
#
acre_foot		S 1.233489e3 m3	# but `acre foot' is 1233.4867714897 meters^3. Odd.
board_foot		S 2.359737e-3 m3
bushel			P 3.523907e-2 m3
UK_liquid_gallon	P 4.546090e-3 m3	# exact. was 4.546092e-3
Canadian_liquid_gallon	P 4.546090e-3 m3	# exact
US_dry_gallon		P 4.404884e-3 m3
US_liquid_gallon	P 3.785412e-3 m3
cc			S cm3
liter			P 1e-3 m3		# exact. However, from 1901 to 
#						# 1964, 1 liter = 1.000028 dm3
stere			P 1 m3			# exact
register_ton		P 2.831685 m3		# was 3.831685 (typo!)

US_dry_quart		P US_dry_gallon/4
US_dry_pint		P US_dry_gallon/8

US_liquid_quart		P US_liquid_gallon/4
US_liquid_pint		P US_liquid_gallon/8
US_liquid_cup		P US_liquid_gallon/16
US_liquid_gill		P US_liquid_gallon/32
US_fluid_ounce		P US_liquid_gallon/128
US_liquid_ounce		P US_fluid_ounce

UK_liquid_quart		P UK_liquid_gallon/4
UK_liquid_pint		P UK_liquid_gallon/8
UK_liquid_cup		P UK_liquid_gallon/16
UK_liquid_gill		P UK_liquid_gallon/32
UK_fluid_ounce		P UK_liquid_gallon/160
UK_liquid_ounce		P UK_fluid_ounce

liquid_gallon		P US_liquid_gallon
fluid_ounce		P US_fluid_ounce
#liquid_gallon		P UK_liquid_gallon
#fluid_ounce		P UK_fluid_ounce

dry_quart		P US_dry_quart
dry_pint		P US_dry_pint

liquid_quart		P liquid_gallon/4
liquid_pint		P liquid_gallon/8

gallon			P liquid_gallon
barrel			P 42 US_liquid_gallon	# petroleum industry definition
quart			P liquid_quart
pint			P liquid_pint
cup			P liquid_gallon/16
gill			P liquid_gallon/32
tablespoon		P US_fluid_ounce/2
teaspoon		P tablespoon/3
peck			P bushel/4

oz			P fluid_ounce
floz			S fluid_ounce
acre_feet		S acre_foot
board_feet		S board_foot
Tbl			P tablespoon
Tbsp			S tablespoon
tbsp			S tablespoon
Tblsp			S tablespoon
tblsp			S tablespoon
litre			P liter
L			S liter
l			S liter
tsp			S teaspoon
pk			S peck
bu			S bushel

fldr			S floz/8
dram			P floz/16

bbl			S barrel
firkin			P barrel/4		# exact but barrel is vague
pt			S pint
dr			S dram


#
# COMPUTERS AND COMMUNICATION
#
baud			S 1/second		# exact
b			S bit
bps			S bit/second
cps			S hertz

Bd			S baud

#
# MISC
#
kayser			P 1e2/meter		# exact
rps			S hertz
rpm			S hertz/60
geopotential		S gravity
work_year		P 2056 hours
work_month		P work_year/12

gp			S geopotential
dynamic			S geopotential