Definition of "Offstage" :

noun: a stage area out of sight of the audience

adjective: situated or taking place in the area of a stage not visible to the audience

"Offstage noises."

adjective: concealed from public view or attention

"Offstage political meetings."

adverb: not in public

"The deal was done offstage."

adverb: behind the scenes; not on stage

"The actors were waiting offstage."