Definition of windmill
(Entry 1 of 2)
1a
: a mill or machine operated by the wind usually acting on oblique vanes or sails that radiate from a horizontal shaft
especially
: a wind-driven water pump or electric generator
b
: the wind-driven wheel of a windmill
2
: something that resembles or suggests a windmill
especially
: a calisthenic exercise that involves alternately lowering each outstretched hand to touch the toes of the opposite foot
3
[from the episode in Don Quixote by Cervantes in which the hero attacks windmills under the illusion that they are giants]
: an imaginary wrong, evil, or opponent
—usually used in the phrase to tilt at windmills
windmill
verb
windmilled; windmilling; windmills
Definition of windmill (Entry 2 of 2)
: to cause to move like a windmill
: to move like a windmill
especially
: to spin from the force of wind
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Merriam-Webster unabridged
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Time Traveler for windmill
The first known use of windmill was in the 13th century
See more words from the same century