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not

adv. · interj. · n.
US //ˈnɑt// UK //nˈɒt// not
  1. 1 negation (adv.)
    A1 Beginner

    you use this to make a word or sentence negative.

    the primary particle used to negate the meaning of a modified verb, adjective, or adverb.

    Example

    She is not coming to the party tonight because she is tired.

    Example

    The results were not as conclusive as the researchers had initially hoped, necessitating a second round of testing.

    Usage

    usually follows an auxiliary verb or 'be'; contracted to n't in informal speech.
    Pitfall
    I not like coffee.
    I do not like coffee.

    In modern English, 'not' usually needs a helping verb like 'do', 'be', or 'have' when negating a main verb.

  2. 2 opposite or understatement (adv.)
    B1 Intermediate

    used to show the opposite of something, often to be polite or less direct.

    used to indicate the opposite or near-opposite of a quality, often functioning as a form of litotes or understatement.

    Example

    The food was not bad, but it was a bit expensive.

    Example

    It was not the most professional response, though it certainly addressed the client's immediate concerns.

    Teacher's tip

    Common in phrases like 'not bad' or 'not exactly' to soften a statement.
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  1. 3 sarcasm (interj.)
    B2 Upper Intermediate Slang Informal

    used at the end of a sentence to show you were joking or being sarcastic.

    used as a post-positioned particle to signal that the preceding statement was intended ironically or sarcastically.

    Example

    I really love doing extra homework on a Friday night... not.

    Example

    Oh sure, I'd love to spend my entire weekend filing these papers... not.

    Usage

    placed at the very end of a sentence after a brief pause.

    Teacher's tip

    This usage was very popular in the 1990s; it is still understood but can feel slightly dated to younger speakers.
    • just kidding
  2. 4 logical operator (n.)
    C1 Advanced Technical Computing

    a rule in math or computers that changes 'true' to 'false'.

    a unary operator that performs logical negation, inverting the truth value of its operand.

    Example

    The computer uses a NOT gate to flip the signal from on to off.

    Example

    The algorithm applies a NOT operation to the boolean variable to ensure the loop terminates correctly.

    Usage

    often written in all capitals (NOT) in programming and logic contexts.
Origin

From Middle English not, nat, variant of noght, naht (“not, nothing”), from Old English *nōht, nāht (“nought, nothing”), short for nōwiht, nāwiht (“nothing”, literally “not anything”), corresponding to ne (“not”) + ōwiht, āwiht (“anything”), corresponding to ā (“ever, always”) + wiht (“thing, creature”). Cognate with Scots nat, naucht (“not”), Saterland Frisian nit (“not”), West Frisian net (“not”), Dutch niet (“not”), German nicht (“not”). Compare nought, naught and aught. More at no, wight, whit.

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