hook up vs hookup

hook up is not a noun while hookup is a noun.

Word	Noun	Adjective	Verb	Adverb
hook up	No	No	Yes	No
hookup	Yes	No	No	No

hook up (noun)	hookup (noun)
	a system of components assembled together for a particular purpose
	a device providing a connection between a power source and a user

hook up (verb)	hookup (verb)
connect or link