- a person who threshes
- threshing machine
- any of a family (Alopiidae, order Lamniformes) of large sharks of temperate and tropical seas, having a very long upper tail lobe, which supposedly threshes the water and drives its prey together
- One that threshes: a thresher of grain.
- A threshing machine.
- A thresher shark.
- (agriculture) Anything or anyone that threshes.
- (agriculture) A modern farm machine for threshing grain, now a part of combine harvesters rather than a separate implement.
- (zoology) Any of several large pelagic sharks of the genus Alopias, which have a very long tail; more commonly called thresher sharks. [from 1880s]
thresh +"Ž -er. The shark's tail is thought to resemble the implement.