"Background dancers" refers to performers who accompany and support the main artist or group during a musical or dance performance. They typically provide visual enhancement and add movement to the overall stage production.
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Other times, Kelly says entire corps de ballet — essentially,
the background dancers — would perish by fire.
Despite the number, the monologue did feel a bit off - beat with the funniest gag being
his background dancers mimicking his every move as he performed his bits.
Anytime you're going to try and do a carefully choreographed scene involving many extras, a band, and
background dancers, you've got to rehearse.
So when we arrived on the soundstage, we saw Jena Malone and
the background dancers working on their moves in anticipation of filming later on in the evening.