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roof

n. · v.
US //ˈɹuf// UK //ɹˈuːf// roof
  1. 1 top of a building (n.)
    A2 Elementary

    the outside part that covers the top of a building or house.

    the external upper covering of a building, designed to provide protection against the elements.

    Example

    The rain was hitting the roof so loudly that we couldn't hear the television.

    Example

    The architect specified a slate roof to ensure the new extension matched the aesthetic of the original Victorian manor.

  2. 2 top of a vehicle (n.)
    A2 Elementary

    the top part of a car, bus, or train.

    the upper surface of a vehicle, often used for storage or structural integrity.

    Example

    We strapped our bicycles to the roof of the car before driving to the mountains.

    Example

    The convertible features a retractable hardtop roof that can be lowered in under twenty seconds while the vehicle is in motion.

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  1. 3 upper part of a cavity (n.)
    B2 Upper Intermediate

    the top inside surface of something, like your mouth or a cave.

    the interior upper surface of a hollow structure or anatomical cavity.

    Example

    He burned the roof of his mouth because the pizza was too hot.

    Example

    The explorers marvelled at the stalactites hanging from the roof of the limestone cavern, some of which reached nearly to the floor.

  2. 4 mining/geology (n.)
    C2 Proficiency Technical Science

    the rock layer directly above a tunnel or a layer of coal.

    the rock layer immediately overlying a mineral seam or underground gallery.

    Example

    The miners had to install extra supports to keep the roof from falling.

    Example

    Geological surveys indicated that the shale roof above the coal seam was unstable, necessitating a change in the extraction method.

    • overburden
  3. 5 to provide a cover (v.)
    B2 Upper Intermediate

    to build or put a roof on a building.

    to cover a structure with a roof; often used in the passive voice to describe a finished building.

    Example

    The workers finished roofing the new house just before the winter started.

    Example

    The stadium is roofed with a translucent material that allows natural light to reach the grass while protecting spectators from rain.

    Usage

    Often used as a past participle or in the passive voice.

Etymology 1

From Middle English rof, from Old English hrōf (“roof, ceiling; top, summit; heaven, sky”), from Proto-Germanic hrōfą (“roof”). Cognate with Scots ruif (“roof, ceiling”), Dutch roef (“cabin on a boat”), Icelandic hróf (“shed”), Irish cró (“pen, barn, cabin”), Proto-Slavic stropъ (“roof, ceiling”). Compare Faroese rógv (“something high up”).

Etymology 2

From Middle English rofen, roven (“to roof”), from the noun (see above).

Word family
Idioms6 entries

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