Imperial Units (Weights and Measures)Edit
14lbs make one stone.
The Imperial system started as a roman unit as Latin. Pondus meaning weight and abbreviated as lb, again Latin for libra, meaning scales or balance. Currently the British have converted to the Metric system using Kilos.
There are also other forms of pound, such as troy, tower, Avoirdupois, London etc. Some exist still and others are just for historical use and comparison. There are also variation for gold, wax and wool.