Pronunciation: (rā'sur), [key]
1. a person, animal, or thing that races or takes part in a race, as a racehorse, bicycle, yacht, etc.
2. anything having great speed.
3. See racing skate.
4. a turntable on which a heavy gun is turned.
5. any of several slender, active snakes of the genera Coluber and Masticophis.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.