lineup vs line up

lineup is a noun but line up is not a noun.

Word	Noun	Adjective	Verb	Adverb
lineup	Yes	No	No	No
line up	No	No	Yes	No

lineup (noun)	line up (noun)
(baseball) a list of batters in the order in which they will bat
the schedule of programs for a particular period
a line of persons arranged by police for inspection or identification

lineup (verb)	line up (verb)
	place in a line or arrange so as to be parallel or straight
	take one's position before a kick-off
	arrange in ranks
	form a queue, form a line, stand in line
	get something or somebody for a specific purpose
	form a line