backing

A backing vocalist or backup singer is a singer who provides vocal harmony with the lead vocalist or other backing vocalists. A backing vocalist may also sing alone as a lead-in to the main vocalist's entry or to sing a counter-melody. Backing vocalists are used in a broad range of popular music, traditional music, and world music styles.
Solo artists may employ professional backing vocalists in studio recording sessions as well as during concerts. In many rock and metal bands (e.g., the power trio), the musicians doing backing vocals also play instruments, such as guitar, electric bass, drums or keyboards. In Latin or Afro-Cuban groups, backing singers may play percussion instruments or shakers while singing. In some pop and hip hop groups and in musical theater, they may be required to perform dance routines while singing through headset microphones.
Styles of background vocals vary according to the type of song and genre of music. In pop and country songs, backing vocalists may sing harmony to support the lead vocalist. In hardcore punk or rockabilly, other band members who play instruments may sing or shout backing vocals during the chorus (refrain) section of the songs.

View More On Wikipedia.org