to take people's attention away from someone and make them listen to or look at you instead

Most supporting bands tend to be youngsters, and rarely upstage the star. 大多数助兴乐队由年轻乐手组成，很少会抢歌星的风头。

towards or at the part of a theatre stage that is furthest from the people watching the performance

He looks upstage to where the body is lying. 他向舞台后部尸体躺着的地方看去。