athlete's foot vs roundworm

athlete's foot and roundworm both are nouns.

Word	Noun	Adjective	Verb	Adverb
athlete's foot	Yes	No	No	No
roundworm	Yes	No	No	No

As nouns, roundworm is a hypernym of athlete's foot; that is, roundworm is a word with a broader meaning than athlete's foot:

athlete's foot: fungal infection of the feet
roundworm: infections of the skin or nails caused by fungi and appearing as itching circular patches

Other hypernyms of athlete's foot include ringworm, tinea.

athlete's foot (noun)	roundworm (noun)
fungal infection of the feet	unsegmented worms with elongated rounded body pointed at both ends; mostly free-living but some are parasitic
	infections of the skin or nails caused by fungi and appearing as itching circular patches