Officiant
An officiant is someone who officiates (i.e. leads) at a service or ceremony, such as marriage, burial, or namegiving/baptism.
Religious Officiants are usually ordained by a religious denomination as members of the clergy. Some officiants work within congregations in some denominations and for specified ceremonies (e.g. funerals), as non-ordained members on the clergy team. Clergy / Officiants differ from Chaplains in that the clergy serve the members of their congregation, while Chaplains are usually employed by an institution such as the military, a hospital or other health care facility, etc.