enclosed space vs pouch

enclosed space and pouch both are nouns.

Word	Noun	Adjective	Verb	Adverb
enclosed space	Yes	No	No	No
pouch	Yes	No	Yes	No

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

Other hyponyms of enclosed space include hollow, pocket, sac, sack.

enclosed space (noun)	pouch (noun)
space that is surrounded by something	a small or medium size container for holding or carrying things
	(anatomy) saclike structure in any of various animals (as a marsupial or gopher or pelican)
	an enclosed space

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