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submarine

n. · adj. · v.
US //ˈsəbmɝˌin// UK //sˈʌbməɹˌiːn// sub·ma·rine
  1. 1 underwater vessel (n.)
    A2 Elementary

    a ship that can travel deep under the ocean for a long time.

    a naval vessel capable of independent operation underwater, typically used for military or research purposes.

    Example

    The submarine stayed under the water for three months without coming up.

    Example

    Modern nuclear submarines are capable of remaining submerged for months at a time, limited only by the food supplies required for the crew.

  2. 2 a long sandwich (n.)
    B1 Intermediate American English Informal Cooking

    a long bread roll filled with meat, cheese, and vegetables.

    a large sandwich consisting of a long crusty roll split lengthwise and filled with various meats and cheeses.

    Example

    I ordered a turkey submarine with extra pickles for lunch.

    Example

    The local deli is famous for its massive submarines, which are packed with imported Italian meats and a signature vinaigrette.

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  1. 3 underwater (adj.)
    B2 Upper Intermediate Science

    happening or existing beneath the surface of the sea.

    existing, occurring, or used under the surface of the sea.

    Example

    Scientists are studying submarine volcanoes to see how they change the ocean floor.

    Example

    The company specialises in the maintenance of submarine cables that provide high-speed internet across the Atlantic.

  2. 4 to slide under (v.)
    C1 Advanced Technical Technical

    to slide forward and under something, like a seatbelt during a car crash.

    to slide forward underneath a restraint, such as a lap belt, during a sudden deceleration or collision.

    Example

    The crash test dummy started to submarine because the seatbelt was too loose.

    Example

    Engineers redesigned the seat base to prevent passengers from submarining during a high-impact frontal collision.

    Usage

    The verb is intransitive in this safety-testing context.

Origin

From sub- + marine.

Idioms1 entry

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