Definition of: thrash

(thrash) v.t.
1. To thresh, as grain.
2. To beat as if with a flail; flog; whip.
3. To defeat utterly.
—v.i.
4. To move or swing about with flailing, violent motions.
5. Naut. To work to windward, against the tide, etc. See synonyms under BEAT.
—to thrash out To discuss fully and to a conclusion.
—noun
1. The act of thrashing.
2. In swimming, a kick used with the crawl and back strokes. [Dial. var. of THRESH]