Orig: probably ultimately from the base of 3433 (through the idea of hardship); a "mill", i.e. (by implication), a grinder (millstone):--millstone. G3433
1) a mill stone 1a) a large mill consisted of two stones, an upper and an under one 1b) the "nether" stone was stationary, but the upper one was turned by an ass 2) a mill, the noise made by a mill