A stone is a British unit of weight that is equivalent to 14 pounds or 6.35 kilograms. It was traditionally used in many northwestern European countries as a unit of weight for dry goods, but it is now commonly used to express body weight in Britain.
The term "stone" originated from using stones as weights in the trade of goods. A stone was chosen as a local standard. As a result, the size and weight of the stones varied by region and by goods being traded, ranging from 4 to 40 pounds. The introduction of the metric system resulted in the stone being replaced by the kilogram.