wind·mill (wĭnd'mĭl')
n.

1. A machine that runs on the energy generated by a wheel of adjustable blades or slats rotated by the wind.
2. Something, such as a toy pinwheel, that is similar to a windmill in appearance or operation.

intr. & tr.v., -milled, -mill·ing, -mills.
To move or cause to move like the wheel of a windmill; rotate sweepingly.

idiom:

tilt at windmills

1. To confront and engage in conflict with an imagined opponent or threat.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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