A door is a moving structure that when closed acts as a barrier to a room, house, building, or car. You'll have to open the door to let your dog come inside.

Buildings have doors, and so do most vehicles. You might also have a special little door built into your own back door for your cat. Doors act as security, as they can be closed and locked, and also as ventilation when you open the door to let the spring air in. Being "out of doors" means you're outside, beyond all the doors of your house or building.

Definitions of door
  1. noun
    a swinging or sliding barrier that will close the entrance to a room or building or vehicle
    “he knocked on the door
    “he slammed the door as he left”
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    car door
    the door of a car
    cargo door
    door used to load or unload cargo
    double door
    two vertical doors that meet in the middle of the door frame when closed
    fire door
    a fire-resistant door that can be closed to stop the spread of a fire
    French door
    a light door with transparent or glazed panels extending the full length
    interior door
    a door that closes off rooms within a building
    revolver, revolving door
    a door consisting of four orthogonal partitions that rotate about a central pivot; a door designed to equalize the air pressure in tall buildings
    screen, screen door
    a door that consists of a frame holding metallic or plastic netting; used to allow ventilation and to keep insects from entering a building through the open door
    sliding door
    a door that opens by sliding instead of swinging
    storm door
    an extra outer door for protection against severe weather or winter
    swing door, swinging door
    a door that swings on a double hinge; opens in either direction
    trap door
    a hinged or sliding door in a floor or ceiling
    barn door
    the large sliding door of a barn
    one of a pair of swinging doors (as at the entrance to a western saloon)
    bi-fold door
    an interior door
    accordion door, folding door
    an interior door that opens by folding back in sections (rather than by swinging on hinges)
    French window
    a French door situated in an exterior wall of a building
    hatchback, hatchback door
    a sloping rear car door that is lifted to open
    type of:
    movable barrier
    a barrier that can be moved to allow passage
  2. noun
    the entrance (the space in a wall) through which you enter or leave a room or building; the space that a door can close
    synonyms: doorway, room access, threshold
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    exterior door, outside door
    a doorway that allows entrance to or exit from a building
    back door, back entrance, backdoor
    an entrance at the rear of a building
    Dutch door, half door
    an exterior door divided in two horizontally; either half can be closed or open independently
    front door, front entrance
    exterior door (at the entrance) at the front of a building
    side door, side entrance
    an exterior door at one side of a building
    type of:
    entrance, entranceway, entree, entry, entryway
    something that provides access (to get in or get out)
  3. noun
    anything providing a means of access (or escape)
    “we closed the door to Haitian immigrants”
    “education is the door to success”
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    open door
    freedom of access
    type of:
    access, accession, admission, admittance, entree
    the right to enter
  4. noun
    a structure where people live or work (usually ordered along a street or road)
    “the office next door
    “they live two doors up the street from us”
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    type of:
    construction, structure
    a thing constructed; a complex entity constructed of many parts
  5. noun
    a room that is entered via a door
    “his office is the third door down the hall on the left”
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    type of:
    an area within a building enclosed by walls and floor and ceiling
Word Family

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