The Collaborative International Dictionary of English v.0.48:
Whim \Whim\, n. [Cf. Icel. hwima to wander with the eyes, vim
giddiness, Norw. kvima to whisk or flutter about, to trifle,
Dan. vimse to skip, whisk, jump from one thing to another,
dial. Sw. hvimsa to be unsteady, dizzy, W. chwimio to move
1. A sudden turn or start of the mind; a temporary
eccentricity; a freak; a fancy; a capricious notion; a
humor; a caprice.
Let every man enjoy his whim. --Churchill.
2. (Mining) A large capstan or vertical drum turned by horse
power or steam power, for raising ore or water, etc., from
mines, or for other purposes; -- called also whim gin,
Whim gin (Mining), a whim. See Whim, 2.
Whim shaft (Mining), a shaft through which ore, water,
etc., is raised from a mine by means of a whim.
Syn: Freak; caprice; whimsey; fancy.
Usage: Whim, Freak, Caprice. Freak denotes an
impulsive, inconsiderate change of mind, as by a child
or a lunatic. Whim is a mental eccentricity due to
peculiar processes or habits of thought. Caprice is
closely allied in meaning to freak, but implies more
definitely a quality of willfulness or wantonness.