cataract vs falls

cataract and falls both are nouns.

Word	Noun	Adjective	Verb	Adverb
cataract	Yes	No	No	No
falls	Yes	No	No	No

As nouns, falls is a hypernym of cataract; that is, falls is a word with a broader meaning than cataract:

Other hypernyms of cataract include waterfall.

cataract (noun)	falls (noun)
a large waterfall; violent rush of water over a precipice	a steep descent of the water of a river
an eye disease that involves the clouding or opacification of the natural lens of the eye	the petals or sepals of a flower that bend downward (especially the outer perianth of an iris)