loon vs do-nothing

loon and do-nothing both are nouns.

Word	Noun	Adjective	Verb	Adverb
loon	Yes	No	No	No
do-nothing	Yes	Yes	No	No

As nouns, do-nothing is a hypernym of loon; that is, do-nothing is a word with a broader meaning than loon:

Other hypernyms of loon include bum, idler, layabout, loafer.

loon (noun)	do-nothing (noun)
large somewhat primitive fish-eating diving bird of the Northern Hemisphere having webbed feet placed far back; related to the grebes	person who does no work
a worthless lazy fellow
a person with confused ideas; incapable of serious thought

loon (adjective)	do-nothing (adjective)
	characterized by inability or unwillingness to work toward a goal or assume responsibility