crossed eye vs strabismus

crossed eye and strabismus both are nouns.

Word	Noun	Adjective	Verb	Adverb
crossed eye	Yes	No	No	No
strabismus	Yes	No	No	No

As nouns, strabismus is a hypernym of crossed eye; that is, strabismus is a word with a broader meaning than crossed eye:

crossed eye: strabismus in which one or both eyes turn inward toward the nose
strabismus: abnormal alignment of one or both eyes

Other hypernyms of crossed eye include squint.

crossed eye (noun)	strabismus (noun)
strabismus in which one or both eyes turn inward toward the nose	abnormal alignment of one or both eyes