Away from the main performance area in a theater or film; private or hidden from public view.
From off- (away from) + stage. Theatrical term that entered English in the 1800s; the metaphorical sense 'private' developed in the 20th century.
The phrase 'offstage behavior' became crucial to celebrity culture in the 1950s-60s as paparazzi revealed that public personas often completely contradicted private lives, birthing modern celebrity scandals.
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