arcus senilis vs cornea

arcus senilis and cornea both are nouns.

Word	Noun	Adjective	Verb	Adverb
arcus senilis	Yes	No	No	No
cornea	Yes	No	No	No

As nouns, cornea is a hypernym of arcus senilis; that is, cornea is a word with a broader meaning than arcus senilis:

arcus senilis: a whitish deposit in the shape of an arc that is sometimes seen in the cornea
cornea: the transparent dome-shaped anterior portion of the outer covering of the eye; it covers the iris and pupil and is continuous with the sclera

arcus senilis (noun)	cornea (noun)
a whitish deposit in the shape of an arc that is sometimes seen in the cornea	the transparent dome-shaped anterior portion of the outer covering of the eye; it covers the iris and pupil and is continuous with the sclera