transitive verb1 a: to drive away the chaff of (grain) by means of a current of air b: to eliminate (as chaff) by winnowing 2: to move or impel (air) with a fan 3: to blow or breathe upon <the breeze fanning her hair> 4 a: to direct a current of air upon with a fan b: to stir up to activity as if by fanning :stimulate<fanning the fires of nationalism> 5archaic:wave 6slang:spank 7: to spread like a fan <the peacock fanned his tail> 8: to strike (a batter) out in baseball 9: to fire a series of shots from (a single-action revolver) by holding the trigger back and successively striking the hammer to the rear with the free handintransitive verb1: to move like a fan :flutter 2: to spread like a fan —often used with out<the searchers fanned out> 3:strike out 3