closing vs closedown

closing and closedown both are nouns.

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

As nouns, closing and closedown are synonyms defined as:

Other synonyms of closing include closure, shutdown.

closing (noun)	closedown (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

closing (adjective)	closedown (adjective)
final or ending