A carat is a unit of mass applied to pearls and precious stones The word comes from the Greek word keration which in turn comes from an Arabic word meaning?

The Arabic Word is qirat (qeeraat), pl. qararit. It has several meanings, all related to measurement. It can be an inch; a dry measure (1/32 of a qadh, which is 0.064 of a litre); a square measure (1/24 of a feddan, which is 175.035 m squared — it's used like 'acre'); and a kerat, a weight (1/16 of a dirham, which is 0.195 of a gram). The source for these meanings is Wehr's dictionary.