janitor definition by American Heritage Dictionary
One who attends to the maintenance or cleaning of a building.
Origin: Latin iānitor, doorkeeper, from iānua, door, from iānus, archway; see ei- in Indo-European roots.
Word History: A holiday for janitors ought to take place in January, for both words are linked. In Latin iānus was the word for “archway, gateway, or covered passage” and also for the god of gates, doorways, and beginnings in general. As many schoolchildren know, our month January—a month of beginnings—is named for the god. Latin iānitor, the source of our word janitor and ultimately also from iānus, meant “doorkeeper or gatekeeper.” Probably because iānitor was common in Latin records and documents, it was adopted into English, first being recorded in the sense “doorkeeper” around 1567 in a Scots text. In an early quotation Saint Peter is called “the Janitor of heaven.” The term can still mean “doorkeeper,” but in Scots usage janitor also referred to a minor school official. Apparently this position at times involved maintenance duties and doorkeeping, and the maintenance duties took over the more exalted tasks, giving us the position of janitor as we know it today.