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let - definition and synonyms

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verb     let pronunciation in British English
Word Forms
present tense
present participleletting
past tenselet
past participlelet
  1. 1
    [transitive] to allow something to happen
    let someone/something do something:

    I stepped back and let him pass.

    let someone/something do something:

    Alice’s mum won’t let her come with us.

    let something in/out/through etc:

    Open the windows and let some fresh air into the room.

    There are holes between the stones that let the wind through.

    let someone know (=tell someone):

    Let us know what time you want us to be there.

    let yourself:

    She lets herself be talked into all kinds of schemes.

  2. 2
    [intransitive/transitive] to rent a room, flat, house etc to someone

    The landlord can let at an agreed market rent.

    let something to someone:

    He’s let his cottage to some people from London.

  3. 3
    [transitive] [always in imperative] used for giving an order or instruction
  4. 4
    [transitive] [always in imperative] used for showing that you are angry or tired, and do not care what happens

    Let her do all the work for a change!

  5. 5
    [transitive] [usually in imperative] maths used in mathematics for saying that you are imagining that something is true, usually in order to prove a principle of mathematics

    Let x = 5.

    Let ABC be a triangle.

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