What it means

1. adjective situated or taking place in the area of a stage not visible to the audience
   “offstage noises”
2. adjective concealed from public view or attention
   “offstage political meetings”
3. noun a stage area out of sight of the audience
4. adverb not in public
   “the deal was done offstage”
5. adverb behind the scenes
   “the actors were waiting offstage”