1.somebody, especially a member of a wait staff, who serves food to patrons at a meal
2.utensil, such as a tray, a large spoon, a fork, etc. for serving and taking food from a large dish
3.[sports] the player who starts a game by hitting the ball first in in tennis and volleyball games.
4.an assistant to a roman catholic, anglican, or eastern orthodox priest to perform a religious ceremony.
5.[computer] a computer that controls or performs a particular job for all the computers in a network