bullet vs projectile

bullet and projectile both are nouns.

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

As nouns, projectile is a hypernym of bullet; that is, projectile is a word with a broader meaning than bullet:

bullet: a projectile that is fired from a gun
projectile: a weapon that is forcibly thrown or projected at a targets but is not self-propelled

Other hypernyms of bullet include missile.

bullet (noun)	projectile (noun)
(baseball) a pitch thrown with maximum velocity	a weapon that is forcibly thrown or projected at a targets but is not self-propelled
a projectile that is fired from a gun	any vehicle self-propelled by a rocket engine
a high-speed passenger train

bullet (adjective)	projectile (adjective)
	impelling or impelled forward