lifer vs yard bird

lifer and yard bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
lifer	Yes	No	No	No
yard bird	Yes	No	No	No

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

Other hypernyms of lifer include con, convict, inmate, yardbird.

lifer (noun)	yard bird (noun)
a prisoner serving a term of life imprisonment	a military recruit who is assigned menial tasks
	a person serving a sentence in a jail or prison