kick in vs kick

kick in is not a noun while kick is a noun.

Word	Noun	Adjective	Verb	Adverb
kick in	No	No	Yes	No
kick	Yes	No	Yes	No

kick in (noun)	kick (noun)
	the act of delivering a blow with the foot
	a rhythmic thrusting movement of the legs as in swimming or calisthenics
	the sudden stimulation provided by strong drink (or certain drugs)
	informal terms for objecting
	the backward jerk of a gun when it is fired
	the swift release of a store of affective force

kick in (verb)	kick (verb)
open violently	express complaints, discontent, displeasure, or unhappiness
contribute to some cause	make a goal
enter a particular state	stop consuming
	strike with the foot
	drive or propel with the foot
	spring back, as from a forceful thrust
	thrash about or strike out with the feet
	kick a leg up