heater vs bullet

heater and bullet both are nouns.

Word	Noun	Adjective	Verb	Adverb
heater	Yes	No	No	No
bullet	Yes	No	No	No

As nouns, heater and bullet are synonyms defined as:

Other synonyms of heater include fastball, hummer, smoke.

heater (noun)	bullet (noun)
(baseball) a pitch thrown with maximum velocity	(baseball) a pitch thrown with maximum velocity
device that heats water or supplies warmth to a room	a projectile that is fired from a gun
	a high-speed passenger train