- a unit for measuring the fineness of gold, pure gold being 24 karats fine. Abbreviation: k., kt.
- US and Canadian a measure of the proportion of gold in an alloy, expressed as the number of parts of gold in 24 parts of the alloyAlso spelt (in Britain and certain other countries): carat
variant of carat (q.v.). In U.S., karat is used for “proportion of fine gold in an alloy” and carat for “weight of a precious stone.”