Chatter mark \Chat"ter mark`\ (a) (Mach.) One of the fine undulations or ripples which are formed on the surface of work by a cutting tool which chatters. (b) (Geol.) A short crack on a rock surface planed smooth by a glacier.
chatter mark n 1: marks on a glaciated rock caused by the movement of a glacier 2: a mark made by a chattering tool on the surface of a workpiece