nonstarter vs racehorse

nonstarter and racehorse both are nouns.

Word	Noun	Adjective	Verb	Adverb
nonstarter	Yes	No	No	No
racehorse	Yes	No	No	No

As nouns, racehorse is a hypernym of nonstarter; that is, racehorse is a word with a broader meaning than nonstarter:

nonstarter: a horse that fails to run in a race for which it has been entered
racehorse: a horse bred for racing

Other hypernyms of nonstarter include bangtail, race horse.

nonstarter (noun)	racehorse (noun)
a horse that fails to run in a race for which it has been entered	a horse bred for racing
a person with a record of failing; someone who loses consistently