irrigation vs enema

irrigation and enema both are nouns.

Word	Noun	Adjective	Verb	Adverb
irrigation	Yes	No	No	No
enema	Yes	No	No	No

As nouns, enema is a hyponym of irrigation; that is, enema 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
enema: an injection of a liquid through the anus to stimulate evacuation; sometimes used for diagnostic purposes

Other hyponyms of irrigation include eye-drop, eyedrop, douche, clyster, lavage.

irrigation (noun)	enema (noun)
supplying dry land with water by means of ditches etc	an injection of a liquid through the anus to stimulate evacuation; sometimes used for diagnostic purposes
(medicine) cleaning a wound or body organ by flushing or washing out with water or a medicated solution