tie-up vs tie up

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

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

tie-up (noun)	tie up (noun)
an interruption of normal activity
a social or business relationship

tie-up (verb)	tie up (verb)
	secure with or as if with ropes
	finish the last row
	restrain from moving or operating normally
	secure in or as if in a berth or dock
	invest so as to make unavailable for other purposes