checkout vs check out

checkout is a noun but check out is not a noun.

Word	Noun	Adjective	Verb	Adverb
checkout	Yes	No	No	No
check out	No	No	Yes	No

checkout (noun)	check out (noun)
the act of inspecting or verifying
a counter in a supermarket where you pay for your purchases
the latest time for vacating a hotel room

checkout (verb)	check out (verb)
	examine so as to determine accuracy, quality, or condition
	announce one's departure from a hotel
	try to learn someone's opinions and intentions
	record, add up, and receive payment for items purchased
	withdraw money by writing a check
	trace
	be verified or confirmed; pass inspection