Pound (lb)
Definition: A pound (symbol: lb) is a unit of mass in the imperial and US customary systems. The international avoirdupois pound is defined as exactly 0.45359237 kilograms. There are 16 ounces in a pound and 2,000 pounds in a short ton.
History/origin: The pound traces its origins to the Roman libra pondo, from which both its name and symbol derive. Various versions of the pound existed across different regions and eras until the avoirdupois pound was standardized internationally in 1959.
Current use: The pound is the primary unit of body weight in the United States and is also used in the UK alongside kilograms. It is common in food labeling, aviation, and general commerce in countries that have not fully adopted the metric system.
