pack rat vs scavenger

pack rat and scavenger both are nouns.

Word	Noun	Adjective	Verb	Adverb
pack rat	Yes	No	No	No
scavenger	Yes	No	No	No

As nouns, pack rat and scavenger are synonyms defined as:

pack rat and scavenger: someone who collects things that have been discarded by others

Other synonyms of pack rat include magpie.

pack rat (noun)	scavenger (noun)
any of several bushy-tailed rodents of the genus Neotoma of western North America; hoards food and other objects	any animal that feeds on refuse and other decaying organic matter
someone who collects things that have been discarded by others	someone who collects things that have been discarded by others
	a chemical agent that is added to a chemical mixture to counteract the effects of impurities