scumbag vs dirty dog

scumbag and dirty dog both are nouns.

Word	Noun	Adjective	Verb	Adverb
scumbag	Yes	No	No	No
dirty dog	Yes	No	No	No

As nouns, scumbag and dirty dog are synonyms defined as:

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

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

scumbag (noun)	dirty dog (noun)
a person who is deemed to be despicable or contemptible	a person who is deemed to be despicable or contemptible