win·now / ˈwinō/ • v. 1. [tr.] blow a current of air through (grain) in order to remove the chaff. ∎ remove (chaff) from grain: women winnow the chaff from piles of unhusked rice. ∎ reduce the number in a set of (people or things) gradually until only the best ones are left: the contenders had been winnowed to five. ∎ find or identify (a valuable or useful part of something): amidst this welter of confusing signals, it's difficult to winnow out the truth. ∎ identify and remove (the least valuable or useful people or things): guidelines that would help winnow out those not fit to be soldiers. 2. [intr.] poetic/lit. (of the wind) blow: the autumn wind winnowing its way through the grass. ∎ [tr.] (of a bird) fan (the air) with wings. DERIVATIVES: win·now·er n.