reinforce vs bolster

reinforce is not a noun while bolster is a noun.

Word	Noun	Adjective	Verb	Adverb
reinforce	No	No	Yes	No
bolster	Yes	No	Yes	No

As verbs, bolster is a hyponym of reinforce; that is, bolster is a word with a more specific, narrower meaning than reinforce:

Other hyponyms of reinforce include buttress, line, bolster up, mine.

reinforce (noun)	bolster (noun)
	a pillow that is often put across a bed underneath the regular pillows

reinforce (verb)	bolster (verb)
make stronger	add padding to
strengthen and support with rewards	support and strengthen
	prop up with a pillow or bolster