check out vs checkout

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

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

check out (noun)	checkout (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

check out (verb)	checkout (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