showtime vs get-go

showtime and get-go both are nouns.

Word	Noun	Adjective	Verb	Adverb
showtime	Yes	No	No	No
get-go	Yes	No	No	No

As nouns, showtime and get-go are synonyms defined as:

Other synonyms of showtime include beginning, commencement, first, kickoff, offset, outset, start, starting time.

showtime (noun)	get-go (noun)
the time at which something is supposed to begin	the time at which something is supposed to begin