bum vs stagnate

bum is a noun but stagnate is not a noun.

Word	Noun	Adjective	Verb	Adverb
bum	Yes	Yes	Yes	No
stagnate	No	No	Yes	No

As verbs, stagnate is a hypernym of bum; that is, stagnate is a word with a broader meaning than bum:

Other hypernyms of bum include idle, laze, slug.

bum (noun)	stagnate (noun)
the fleshy part of the human body that you sit on
a vagrant
a person who is deemed to be despicable or contemptible
person who does no work

bum (adjective)	stagnate (adjective)
of very poor quality; flimsy

bum (verb)	stagnate (verb)
ask for and get free; be a parasite	be idle; exist in a changeless situation
be lazy or idle	cease to flow; stand without moving
	stand still
	cause to stagnate