مِرْاةٌ

A mirror: (T, S, M, K:) originally مِرْأَيَةٌ: (Msb:) plural مَرَاءٍ and مَرَايَا; (T, S, Msb;) the latter formed by transmutation [of the ء into ى]. (T. [It is said in the S, that the former plural is used in speaking of three; and the latter, in speaking of many; but for this distinction I see no reason: and in the Msb it is said that, according to Az, the latter plural is a mistake; but this I do not find in the T.])