monofocal IOL vs lens implant

monofocal IOL and lens implant both are nouns.

Word	Noun	Adjective	Verb	Adverb
monofocal IOL	Yes	No	No	No
lens implant	Yes	No	No	No

As nouns, lens implant is a hypernym of monofocal IOL; that is, lens implant is a word with a broader meaning than monofocal IOL:

monofocal IOL: a lens with a single focus that is used after cataract surgery to provide clear distance vision
lens implant: a clear plastic lens that is implanted in the eye; usually done when the natural lens has been removed in a cataract operation

Other hypernyms of monofocal IOL include interocular lens implant, IOL.

monofocal IOL (noun)	lens implant (noun)
a lens with a single focus that is used after cataract surgery to provide clear distance vision	a clear plastic lens that is implanted in the eye; usually done when the natural lens has been removed in a cataract operation