carry over vs carry-over

carry over is not a noun while carry-over is a noun.

Word	Noun	Adjective	Verb	Adverb
carry over	No	No	Yes	No
carry-over	Yes	No	No	No

carry over (noun)	carry-over (noun)
	application of a skill learned in one situation to a different but similar situation
	the accumulated and undivided profits of a corporation after provision has been made for dividends and reserves

carry over (verb)	carry-over (verb)
transfer or persist from one stage or sphere of activity to another
transfer from one time period to the next
transport from one place or state to another
hold over goods to be sold for the next season