undercut vs cut away

undercut is a noun but cut away is not a noun.

Word	Noun	Adjective	Verb	Adverb
undercut	Yes	No	Yes	No
cut away	No	No	Yes	No

As verbs, cut away is a hypernym of undercut; that is, cut away is a word with a broader meaning than undercut:

As verbs, cut away is a hypernym of undercut; that is, cut away is a word with a broader meaning than undercut:

undercut: cut away material from the underside of (an object) so as to leave an overhanging portion in relief
cut away: remove by cutting off or away

undercut (noun)	cut away (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

undercut (verb)	cut away (verb)
strike (the ball) in golf, tennis, or hockey obliquely downward so as to give a backspin or elevation to the shot	remove by cutting off or away
cut away the underpart of	move quickly to another scene or focus when filming
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
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