close down vs shut down

close down and shut down both are verbs.

Word	Noun	Adjective	Verb	Adverb
close down	No	No	Yes	No
shut down	No	No	Yes	No

As verbs, close down and shut down are synonyms defined as:

Other synonyms of close down include close, close up, fold.

close down (verb)	shut down (verb)
cease to operate or cause to cease operating	cease to operate or cause to cease operating