ردس

مِرْدَسٌ ذ A hard thing with which a thing is beaten so as to be broken, or crushed, thereby: (M:) and ↓ مِرْدَاسٌ signifies [in like manner] a big stone with which a thing is so beaten: (A:) or each, a hard and broad thing with which a wall and the ground (K, TA) and a lump of dry clay (TA) are so beaten: (K, TA:) or the latter word, a mass of stone, or rock, which one throws; and the former has this meaning also, as well as the first meaning: (M:) or the latter word, (S,) or each, (M,) a stone which is thrown into a well in order that one may know whether there be in it water or not. (S, M. [See also مِرْجَاسٌ.])