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mad

adj. · adv.
US //ˈmæd// UK //mˈæd// mad
  1. 1 mentally ill (adj.)
    B1 Intermediate British English

    having a mind that does not work in a healthy way; mentally ill.

    suffering from a mental illness or being extremely foolish. This is the primary sense in British English.

    Example

    The old stories tell of a king who went mad and talked to the trees.

    Example

    In nineteenth-century literature, characters were often described as going mad when they could no longer cope with social pressures.

    Usage

    Often used in the phrase 'go mad'.

    Teacher's tip

    In modern contexts, using this to describe mental health can be seen as insensitive; 'mentally ill' is the neutral alternative.
  2. 2 very enthusiastic (adj.)
    B1 Intermediate Informal

    liking something very much or being very excited about it.

    extremely enthusiastic about or fond of something.

    Example

    My brother is mad about football and never misses a game.

    Example

    She was mad about jazz in her youth, spending every spare penny on vinyl records and concert tickets.

    Usage

    Usually followed by the preposition 'about'.
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  1. 3 foolish or irrational (adj.)
    B2 Upper Intermediate

    very silly, stupid, or not making any sense.

    extremely foolish, unwise, or irrational.

    Example

    It was a mad idea to go hiking in the middle of a thunderstorm.

    Example

    The plan to expand the factory without securing extra funding was seen by many as a mad gamble.
  2. 4 very or extremely (adv.)
    C1 Advanced Slang American English

    used to mean 'very' or 'extremely' to make an adjective stronger.

    used as an intensifier to mean 'extremely' or 'very'.

    Example

    That new video game is mad expensive, so I have to save up for it.

    Example

    The concert was mad loud, but the atmosphere was incredible despite the noise levels.
Idioms6 entries

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