Pronunciation: (thresh'ur), [key]
1. a person or thing that threshes.
2. Also,thrasher.Also called thresh'er shark". a large shark of the genus Alopias, esp. A. vulpinus, which threshes the water with its long tail to drive together the small fish on which it feeds.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.