lowlife vs dirty dog

lowlife and dirty dog both are nouns.

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

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

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

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

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