In Christianity, the cantor, female chantress, sometimes called the precentor or the protopsaltes (Greek: πρωτοψάλτης, lit. 'first singer'; from Greek: ψάλτης, romanized: psaltes, lit. 'singer'), is the chief singer, and usually instructor, employed at a church, with responsibilities for the choir and the preparation of the Mass or worship service. The term is also used for a similar task in Reform Judaism and in Ancient Egypt. Generally, a cantor must be competent to choose and conduct the vocals for the choir, to start any chant on demand, and to be able to identify and correct the missteps of singers placed under them. A cantor may be held accountable for the immediate rendering of the music, showing the course of the melody by movements of the hand(s) (cheironomia), similar to a conductor. Source: Wikipedia (en)