rebuff vs cold shoulder

rebuff and cold shoulder both are nouns.

Word	Noun	Adjective	Verb	Adverb
rebuff	Yes	No	Yes	No
cold shoulder	Yes	No	No	No

As nouns, cold shoulder is a hyponym of rebuff; that is, cold shoulder is a word with a more specific, narrower meaning than rebuff:

rebuff: a deliberate discourteous act (usually as an expression of anger or disapproval)
cold shoulder: a refusal to recognize someone you know

Other hyponyms of rebuff include cut, snub, silent treatment.

rebuff (noun)	cold shoulder (noun)
a deliberate discourteous act (usually as an expression of anger or disapproval)	a refusal to recognize someone you know
an instance of driving away or warding off

rebuff (verb)	cold shoulder (verb)
reject outright and bluntly
force or drive back