Quintal

The quintal is an historical unit of mass with many different definitions in different countries. It is derived from the Latin centenarius, meaning 100 pounds. The unit was and still is used in the Arab world, where it is known as the qintar. It is currently defined informally as 50 kg. The qintar was imported to Europe by traders. In France it was defined as 100 livres, about 48.95 kg, although it has now been redefined as 100 kg. In Spain it is still defined as 100 libras, or about 46 kg, and in Portugal as 128 libras or about 58.75 kg. The English quintal, now obsolete, was defined sometimes as 100 lb (exactly 45.359 237 kg) and sometimes as 112 lb (about 50.80 kg).

The metric quintal is defined in the U.S. as 100 kilograms. This unit is not recognised by the SI, but is used in agriculture for measuring grain.