1an animal or means of transport bred or designed for racing:tall-masted ocean racers
a person who competes in races:a car that every top racer wants to drivehe’s Britain’s No 1 downhill racer
[as modifier]another term for racerback.a racer bra
2a fast-moving, harmless, and typically slender-bodied snake.
Several genera in the family Colubridae: genus Coluber, including the American C. constrictor and the European C. gemonensis(see also whip snake), and the Asian genera Ptyas and Argyrogena(also called rat snake)
3a circular horizontal rail along which the carriage or traversing platform of a heavy gun moves.