Clergy is the generic term used to describe the formal religious leadership within a given religion. A clergyman, churchman or cleric is a member of the clergy, especially one who is a priest, preacher, pastor, or other religious professional.
Depending on the religion, clergy usually take care of the ritual aspects of the religious life, teach or otherwise help in spreading the religion’s doctrine and practices. They often deal with events such as childbirth, baptism, circumcision, coming of age ceremonies and death.
In Christianity there is a wide range of formal and informal clergy positions, including deacons, priests, bishops, and ministers. In Shia Islam, religious leaders are usually known as imams or ayatollahs.