The
pound or
pound-mass (abbreviation
lb,
lbm, or sometimes in the United States
_) is a
unit of
mass used in the
imperial,
United States customary and other
systems of measurement. A number of different
definitions have been used, the most common today being the
international avoirdupois pound of exactly
0.45359237&_160;kilogram.The word pound comes from the Latin word pendere, meaning "to weigh". The abbreviation lb comes from the Latin word libra, meaning "scales, balances", which also described a Roman unit similar to the pound.
Historically, in different parts of the world, at different points in time, and for different applications, the pound (or its translation) has referred to broadly similar but not identical standards of mass or weight.
A number of different definitions of the pound have been used in Britain. Amongst these are the avoirdupois pound and the obsolete Troy, tower, merchant's and London pounds.[1]
