(obsolete) A serving boy – a youth attending a person of high degree, especially at courts, as a position of honor and education.
(Britain) A youth employed for doing errands, waiting on the door, and similar service in households.
(US, Canada) A boy or girl employed to wait upon the members of a legislative body.
(in libraries) The common name given to an employee whose main purpose is to replace materials that have either been checked out or otherwise moved, back to their shelves.