n. Abbr. c or car.
1. A unit of weight for precious stones, equal to 200 milligrams.
2. Variant of karat.
[Middle English, from Old French, from Medieval Latin quarātus, from Arabic qīrāṭ, a measure of weight, from Greek kerātion, carob pod, a measure of weight (originally defined in reference to a dried carob seed), from diminutive of keras, kerāt-, horn (from the pod's shape ); see ker-1 in the Appendix of Indo-European roots.]
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