drifter vs bird of passage

drifter and bird of passage both are nouns.

Word	Noun	Adjective	Verb	Adverb
drifter	Yes	No	No	No
bird of passage	Yes	No	No	No

As nouns, bird of passage is a hypernym of drifter; that is, bird of passage is a word with a broader meaning than drifter:

drifter: a wanderer who has no established residence or visible means of support
bird of passage: someone who leads a wandering unsettled life

Other hypernyms of drifter include have-not, poor person, roamer, rover, wanderer.

drifter (noun)	bird of passage (noun)
a wanderer who has no established residence or visible means of support	any bird that migrates seasonally
	someone who leads a wandering unsettled life