What does "racehorse" mean?

A horse that competes in races.

What is a synonym for "racehorse"?

Common synonyms include: athletic horse, bangtail, competitor, participant, race horse, racer.

noun

noun ·2 syllables ·Rare ·Advanced level

Noun

1
A horse that competes in races.
"They were bosker horses. Until I went to work for Bill I didn't know how good racehorses are."
2
a horse bred for racing wordnet

"An investigation established that the racehorse had been doped."

From race + horse.