irrigation vs eye-drop

irrigation and eye-drop both are nouns.

Word	Noun	Adjective	Verb	Adverb
irrigation	Yes	No	No	No
eye-drop	Yes	No	No	No

As nouns, eye-drop is a hyponym of irrigation; that is, eye-drop is a word with a more specific, narrower meaning than irrigation:

irrigation: (medicine) cleaning a wound or body organ by flushing or washing out with water or a medicated solution
eye-drop: a method of irrigating the eye used by ophthalmologists

Other hyponyms of irrigation include eyedrop, douche, clyster, enema, lavage.

irrigation (noun)	eye-drop (noun)
supplying dry land with water by means of ditches etc	a method of irrigating the eye used by ophthalmologists
(medicine) cleaning a wound or body organ by flushing or washing out with water or a medicated solution	a drop from an eye dropper