bum vs scumbag

bum and scumbag both are nouns.

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

As nouns, bum and scumbag are synonyms defined as:

bum and scumbag: a person who is deemed to be despicable or contemptible

Other synonyms of bum include crumb, dirty dog, git, lowlife, puke, rat, rotter, scum bag, skunk, so-and-so, stinker, stinkpot.

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

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

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