ration vs cut back

ration is a noun but cut back is not a noun.

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

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

ration: restrict the consumption of a relatively scarce commodity, as during war
cut back: place restrictions on

Other hypernyms of ration include curb, curtail, restrict.

ration (noun)	cut back (noun)
the food allowance for one day (especially for service personnel)
a fixed portion that is allotted (especially in times of scarcity)

ration (verb)	cut back (verb)
distribute in rations, as in the army	place restrictions on
restrict the consumption of a relatively scarce commodity, as during war	cut down on; make a reduction in
	cultivate, tend, and cut back the growth of
	return in time