Definitions
1.nounA portal of entry into a building, room, or vehicle, consisting of a rigid plane movable on a hinge. Doors are frequently made of wood or metal. May have a handle to help open and close, a latch to hold the door closed and a lock that ensures the door cannot be opened without the key."I knocked on the vice president's door"
2.nounAny flap, etc. that opens like a door."the 24 doors in an Advent calendar"
3.noun(immigration) An entry point.
4.nounA means of approach or access."Learning is the door to wisdom."
5.nounA barrier."Keep a door on your anger."
6.nounA software mechanism by which a user can interact with a program running remotely on a bulletin board system. See BBS door.
7.verbTo cause a collision by opening the door of a vehicle in front of an oncoming cyclist or pedestrian.