workhorse: Meaning and Definition of

work•horse

Pronunciation: (wûrk'hôrs"), [key]
— n.
  1. a horse used for plowing, hauling, and other heavy labor, as distinguished from a riding horse, racehorse, etc.
  2. a person who works tirelessly at a task, assumes extra duties, etc.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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