Choir is also referred to as a chorus.
A choir ( [ ` kwaɪ.ər ] ) ( also known as a chorale or chorus ) is a musical ensemble of singers . A body of singers who perform together as a group is called a choir or chorus . In typical 18th - to 21st-century oratorios and masses , chorus or choir is usually understood to imply more than one singer per part , in contrast to the quartet of soloists also featured in these works .