pes planus vs human foot

pes planus and human foot both are nouns.

Word	Noun	Adjective	Verb	Adverb
pes planus	Yes	No	No	No
human foot	Yes	No	No	No

As nouns, human foot is a hypernym of pes planus; that is, human foot is a word with a broader meaning than pes planus:

pes planus: a foot afflicted with a fallen arch; abnormally flattened and spread out
human foot: the part of the leg of a human being below the ankle joint

Other hypernyms of pes planus include foot, pes.

pes planus (noun)	human foot (noun)
a foot afflicted with a fallen arch; abnormally flattened and spread out	the part of the leg of a human being below the ankle joint