cavity vs pouch

cavity and pouch both are nouns.

Word	Noun	Adjective	Verb	Adverb
cavity	Yes	No	No	No
pouch	Yes	No	Yes	No

As nouns, pouch is a hyponym of cavity; that is, pouch is a word with a more specific, narrower meaning than cavity:

Other hyponyms of cavity include hollow, pocket, sac, sack.

cavity (noun)	pouch (noun)
(anatomy) a natural hollow or sinus within the body	a small or medium size container for holding or carrying things
a sizeable hole (usually in the ground)	(anatomy) saclike structure in any of various animals (as a marsupial or gopher or pelican)
soft decayed area in a tooth; progressive decay can lead to the death of a tooth	an enclosed space
space that is surrounded by something

cavity (verb)	pouch (verb)
	swell or protrude outwards
	put into a small bag
	send by special mail that goes through diplomatic channels