strike down vs undercut

strike down is not a noun while undercut is a noun.

Word	Noun	Adjective	Verb	Adverb
strike down	No	No	Yes	No
undercut	Yes	No	Yes	No

strike down (noun)	undercut (noun)
	(sports) a stroke that puts reverse spin on the ball
	a cut made underneath to remove material
	a notch cut in the trunk of tree in order to determine the direction of its fall
	the tender meat of the loin muscle on each side of the vertebral column
	the material removed by a cut made underneath

strike down (verb)	undercut (verb)
cause to fall by or as if by delivering a blow	strike (the ball) in golf, tennis, or hockey obliquely downward so as to give a backspin or elevation to the shot
cause to die, especially suddenly	cut away the underpart of
declare null and void; make ineffective	cut away material from the underside of (an object) so as to leave an overhanging portion in relief
	cut obliquely into (a tree) below the main cut and on the side toward which the tree will fall
	sell cheaper than one's competition