bristle vs stand up

bristle is a noun but stand up is not a noun.

Word	Noun	Adjective	Verb	Adverb
bristle	Yes	No	Yes	No
stand up	No	No	Yes	No

As verbs, bristle and stand up are synonyms defined as:

Other synonyms of bristle include uprise.

bristle (noun)	stand up (noun)
a stiff hair
a stiff fiber (coarse hair or filament); natural or synthetic

bristle (verb)	stand up (verb)
react in an offended or angry manner	defend against attack or criticism
rise up as in fear	refuse to back down; remain solid under criticism or attack
be in a state of movement or action	be standing; be upright
have or be thickly covered with or as if with bristles	put into an upright position
	rise to one's feet
	rise up as in fear
	resist or withstand wear, criticism, etc.