closedown vs closing

closedown and closing both are nouns.

Word	Noun	Adjective	Verb	Adverb
closedown	Yes	No	No	No
closing	Yes	Yes	No	No

As nouns, closedown and closing are synonyms defined as:

Other synonyms of closedown include closure, shutdown.

closedown (noun)	closing (noun)
termination of operations	termination of operations
	the act of closing something
	a concluding action
	approaching a particular destination; a coming closer; a narrowing of a gap
	the last section of a communication

closedown (adjective)	closing (adjective)
	final or ending