bum vs unpleasant person

bum and unpleasant person both are nouns.

Word	Noun	Adjective	Verb	Adverb
bum	Yes	Yes	Yes	No
unpleasant person	Yes	No	No	No

As nouns, unpleasant person is a hypernym of bum; that is, unpleasant person is a word with a broader meaning than bum:

Other hypernyms of bum include disagreeable person.

bum (noun)	unpleasant person (noun)
the fleshy part of the human body that you sit on	a person who is not pleasant or agreeable
a vagrant
a person who is deemed to be despicable or contemptible
person who does no work

bum (adjective)	unpleasant person (adjective)
of very poor quality; flimsy

bum (verb)	unpleasant person (verb)
ask for and get free; be a parasite
be lazy or idle