A janitor is someone whose job is cleaning and maintaining a building. If your school always looks clean and orderly, be sure to thank the janitor.
Another name for a janitor is a custodian, or in Britain, a caretaker. This job involves cleaning and caring for a school, hospital, apartment building, or workplace. Janitors may be responsible for cleaning bathrooms, hallways, and other common areas. Sometimes janitors will also sweep sidewalks, shovel snow, or do other outdoor maintenance. In the 16th century, a janitor was a "doorkeeper," from the Latin ianitor, "doorkeeper or porter," and the root ianua, "door."