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ought

v. · n.
US //ˈɔt// UK //ˈɔːt// ought
  1. 1 duty or obligation (v.)
    B1 Intermediate Formal

    used to say that someone has a duty to do something because it is the right thing to do.

    expresses moral or legal obligation or duty. It is followed by the 'to'-infinitive and does not change form for person or number.

    Example

    We ought to help our neighbours while they are away on holiday.

    Example

    Citizens ought to consider the long-term environmental consequences of their daily consumption habits before dismissing new regulations.

    Usage

    Always followed by 'to' plus the base form of the verb; in negatives, 'ought not to' is the standard formal construction.

    Pitfall
    You ought go to the doctor.
    You ought to go to the doctor.

    Unlike 'should' or 'must', 'ought' requires 'to' before the following verb.

  2. 2 probability or expectation (v.)
    B2 Upper Intermediate Formal

    used to say that you expect something to happen based on what you know.

    indicates a strong logical probability or expectation that a particular state or event will occur.

    Example

    The bus ought to be here in five minutes if the traffic is light.

    Example

    Given the current economic indicators, the central bank ought to announce a reduction in interest rates by the end of the quarter.

    Usage

    Functions as a modal of deduction, similar to 'should' in its epistemic sense.

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  1. 3 what should be (n.)
    C2 Proficiency Academic Formal

    an idea of what is right or how things should be, rather than how they actually are.

    refers to an ideal state or a moral imperative, often contrasted with 'is' in philosophical contexts.

    Example

    There is often a big difference between the 'is' and the 'ought' in politics.

    Example

    The philosopher spent his career exploring the gap between the 'is' of human nature and the moral 'ought' of ethical theory.

    Teacher's tip

    This noun use is rare outside of academic or philosophical discussions regarding ethics.

Origin

From Middle English oughte, aughte, aȝte, ahte, from Old English āhte, first and third person singular past tense of Old English āgan (“to own, possess”), equivalent to owe + -t. Cognate with Sanskrit ईश्वर (īśvará, “capable of, liable”).

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