cut back vs flash back

cut back and flash back both are verbs.

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

As verbs, cut back and flash back are synonyms defined as:

cut back (verb)	flash back (verb)
place restrictions on	return in time
cut down on; make a reduction in
cultivate, tend, and cut back the growth of
return in time