sexual practice vs suckle

sexual practice is a noun but suckle is not a noun.

Word	Noun	Adjective	Verb	Adverb
sexual practice	Yes	No	No	No
suckle	No	No	Yes	No

sexual practice (noun)	suckle (noun)
activities associated with sexual intercourse

sexual practice (verb)	suckle (verb)
	give suck to
	suck milk from the mother's breasts