To fan; set in motion by means of wind; specifically, to expose (grain) to a current of air in order to separate and drive off chaff, refuse particles, etc.To blow upon; toss about by blowing.To separate, expel, or disperse by or as by fanning or blowing; sift or weed out; separate or distinguish, as one thing from another.To set in motion or vibration; beat as with a fan or wings.To wave to and fro; flutter; flap.To pursue or accomplish with a waving or flapping motion, as of wings.Figuratively, to subject to a process analogous to the winnowing of grain; separate into parts according to kind; sift; analyze or scrutinize carefully; examine; test.To free grain or the like from chaff or refuse matter by means of wind.To move about with a flapping motion, as of wings; flutter.n. That which winnows or which is used in winnowing; a contrivance for fanning or winnowing grain.