from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A simple machine consisting of an axle to which a wheel is fastened so that torque applied to the wheel winds a rope or chain onto the axle, yielding a mechanical advantage equal to the ratio of the diameter of the wheel to that of the axle.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a simple machine consisting of a wheel (or similar lever) that turns an axle around which a cord is wound; its mechanical advantage is the ratio of the diameters of the wheel and axle
from the GNU version of the Collaborative International Dictionary of English
- n. one of the elementary machines or mechanical powers, consisting of a wheel fixed to an axle, and used for raising great weights, by applying the power to the circumference of the wheel, and attaching the weight, by a rope or chain, to that of the axle. Called also axis in peritrochio, and perpetual lever, -- the principle of equilibrium involved being the same as in the lever, while its action is continuous. See Mechanical powers, under Mechanical.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. hoist so arranged that a rope unwinding from a wheel is wound onto a cylindrical drum or shaft coaxial with the wheel
Sorry, no etymologies found.