pull-up vs pull up

pull-up is a noun but pull up is not a noun.

Word	Noun	Adjective	Verb	Adverb
pull-up	Yes	No	No	No
pull up	No	No	Yes	No

pull-up (noun)	pull up (noun)
an arm exercise performed by pulling yourself up on a horizontal bar until your chin is level with the bar
a roadside cafe especially for lorry drivers

pull-up (verb)	pull up (verb)
	remove, usually with some force or effort; also used in an abstract sense
	cause (a vehicle) to stop
	come to a halt after driving somewhere
	straighten oneself