The hundredweight (abbreviation: cwt), formerly also known as the centum weight or quintal, is an English, imperial, and American unit of weight or mass of various values. Its value differs between the American and imperial systems. The two values are distinguished in American English as the "short" and "long" hundredweight and in British English as the "cental" and the "imperial hundredweight".
The hundredweight has had many values. In England in around 1300, different "hundreds" (centum in Medieval Latin) were defined. The Weights and Measures Act 1835 formally established the present imperial hundredweight of 112 lb.
The United States and Canada came to use the term "hundredweight" to refer to a unit of 100 lb. This measure was specifically banned from British use--upon risk of being sued for fraud--by the Weights and Measures Act 1824 but, in 1879, the measure was legalized under the name "cental" in response to legislative pressure from British merchants importing wheat and tobacco from the United States.
A few decades ago, commodities weighed in terms of long hundredweight included cattle, cattle fodder, fertilizers, coal, some industrial chemicals, other industrial materials, and so on. However, since increasing metrication in most English-speaking countries, it is now less used. Church bell ringers use the unit commonly, although church bell manufacturers are increasingly moving over to the metric system.
Older blacksmiths' anvils are often stamped with a three-digit number indicating their total weight in hundredweight, quarter-hundredweight (28 lb, abbreviated qr), and pounds. Thus, an anvil stamped "1.1.8" will weigh 148 lb (112 lb + 28 lb + 8 lb).