rebuff vs freeze off

rebuff is a noun but freeze off is not a noun.

Word	Noun	Adjective	Verb	Adverb
rebuff	Yes	No	Yes	No
freeze off	No	No	Yes	No

As verbs, freeze off is a hypernym of rebuff; that is, freeze off is a word with a broader meaning than rebuff:

Other hypernyms of rebuff include disdain, pooh-pooh, reject, scorn, spurn, turn down.

rebuff (noun)	freeze off (noun)
a deliberate discourteous act (usually as an expression of anger or disapproval)
an instance of driving away or warding off

rebuff (verb)	freeze off (verb)
reject outright and bluntly	reject with contempt
force or drive back