cut back vs shear

cut back is not a noun while shear is a noun.

Word	Noun	Adjective	Verb	Adverb
cut back	No	No	Yes	No
shear	Yes	No	Yes	No

As verbs, shear is a hyponym of cut back; that is, shear is a word with a more specific, narrower meaning than cut back:

Other hyponyms of cut back include poll, pollard, pinch, top, disbud.

cut back (noun)	shear (noun)
	a large edge tool that cuts sheet metal by passing a blade through it
	(physics) a deformation of an object in which parallel planes remain parallel but are shifted in a direction parallel to themselves

cut back (verb)	shear (verb)
place restrictions on	become deformed by forces tending to produce a shearing strain
cut down on; make a reduction in	cut with shears
cultivate, tend, and cut back the growth of	cut or cut through with shears
return in time	shear the wool from