That which winnows or which is used in winnowing; a contrivance for fanning or winnowing grain.
The act of winnowing
To blow upon or toss about by blowing; to set in motion as with a fan or wings.
To separate, sift, analyse, or test by separating items having different values.
To subject (granular material, especially food grain) to a current of air separating heavier and lighter components, as grain from chaff.