hunch over vs hunch

hunch over is not a noun while hunch is a noun.

Word	Noun	Adjective	Verb	Adverb
hunch over	No	No	Yes	No
hunch	Yes	No	Yes	No

As verbs, hunch over and hunch are synonyms defined as:

hunch over and hunch: round one's back by bending forward and drawing the shoulders forward

Other synonyms of hunch over include hump, hunch forward.

hunch over (noun)	hunch (noun)
	the act of bending yourself into a humped position
	an impression that something might be the case

hunch over (verb)	hunch (verb)
round one's back by bending forward and drawing the shoulders forward	round one's back by bending forward and drawing the shoulders forward