To subject (granular material, especially food grain) to a current of air separating heavier and lighter components, as grain from chaff.
To separate, sift, analyze, or test by separating items having different values.
Example: "They winnowed the field to twelve."
To blow upon or toss about by blowing; to set in motion as with a fan or wings.
To move about with a flapping motion, as of wings; to flutter.