What is the meaning of Carat?

A metric unit of weight equal to exactly 200 mg, chiefly used for measuring precious stones and pearls .

Any of several small units of weight used for measuring precious stones and pearls, equivalent to 189212 mg.

A 24-point scale used to measure the purity of gold.

carat

carat (measure of purity of gold)

genitive singular/plural of cara (friend; relative)

genitive singular/dual/plural of cara

carat, karat

Source: wiktionary.org