backup singer
backing vocalist
back singer

Melanie has been a backing vocalist in her father's band since 2002.

Casey was the backing vocalist who used death growls in the songs.

By 1983 she had returned to her earlier career as a backing vocalist.

For many years she was a backing vocalist for Madonna.

She later became a backing vocalist for other Dutch acts.

Lee was a backing vocalist for the pop group Wham!

She has had a successful career as a backing vocalist and dancer for many artists around the world.

Hoopes has been the primary backing vocalist for the band ever since.

Stevvi has been a backing vocalist on many tours since the late 90's.

In the early years, Jones often served as a backing vocalist.