IPA: /ˈɒfˌsteɪdʒ/
KK: /ˈɔfˌsteɪdʒ/
Relating to or happening in a part of a stage that the audience cannot see, or in private life away from public view.
The actor's offstage behavior was very different from his onstage persona.
In a manner that is not visible to the audience or public, typically referring to actions or events that occur behind the scenes.
The actors prepared offstage before their big performance.
Offstage → It is formed from "off" (meaning away from) and "stage" (from Old French *estage*, meaning a platform or stage for performances). The word "offstage" refers to an area away from the main performance area, typically where actors wait or prepare.
Think of being 'away from' ('off') the 'platform' ('stage') where the performance happens — that's what offstage means.