ad. Toward, at, or on the rear part of a stage.adj. Of or relating to the rear part of a stage.adj. Informal Haughty; aloof.n. The rear part of a stage, away from the audience.v. To distract attention from (another performer) by moving upstage, thus forcing the other performer to face away from the audience.v. To divert attention or praise from; force out of the spotlight: a vice president who repeatedly tried to upstage the president. v. To treat haughtily.