shutdown vs closedown

shutdown and closedown both are nouns.

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

As nouns, shutdown and closedown are synonyms defined as:

Other synonyms of shutdown include closing, closure.

shutdown (noun)	closedown (noun)
termination of operations	termination of operations