irrigate vs irrigation

irrigate is not a noun while irrigation is a noun.

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

irrigate (noun)	irrigation (noun)
	supplying dry land with water by means of ditches etc
	(medicine) cleaning a wound or body organ by flushing or washing out with water or a medicated solution

irrigate (verb)	irrigation (verb)
supply with a constant flow or sprinkling of some liquid, for the purpose of cooling, cleansing, or disinfecting
supply with water, as with channels or ditches or streams