Merriam-Webster Collegiate Dictionary - deacon

 noun  Etymology: Middle English dekene, from Old English deacon, from Late Latin diaconus, from Greek diakonos, literally, servant, from dia- + -konos (akin to enkonein to be active); perhaps akin to Latin conari to attempt  Date: before 12th century a subordinate officer in a Christian church: as  a. a Roman Catholic, Anglican, or Eastern Orthodox cleric ranking next below a priest  b. one of the laymen elected by a church with congregational polity to serve in worship, in pastoral care, and on administrative committees  c. a Mormon in the lowest grade of the Aaronic priesthood