ENGLISH
REFERENCE

crazy

adj. · adv. · n.
US //ˈkɹeɪzi// UK //kɹˈeɪzi// crazy
  1. 1 strange or wild (adj.)
    A2 Elementary Informal

    very strange, unusual, or foolish.

    not sensible or logical; extremely foolish or strange.

    Example

    It was a crazy idea to drive through the storm at night.

    Example

    The plan to launch the product without any prior testing seemed crazy to the rest of the board members.
  2. 2 very enthusiastic (adj.)
    A2 Elementary Informal

    liking something or someone very much.

    extremely enthusiastic or fond of a particular person, activity, or object.

    Example

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

    Example

    She has been crazy about jazz since she was a teenager, spending most of her weekends at local clubs.
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  1. 3 mentally ill (adj.)
    B1 Intermediate Informal

    having a mind that does not work in a normal way.

    suffering from a mental illness or being of unsound mind.

    Example

    The old stories say a crazy man used to live in that house.

    Example

    The defendant's lawyers argued that he was crazy at the time of the incident to avoid a prison sentence.

    Usage

    Often considered offensive when used to describe people with clinical mental health conditions.

    Teacher's tip

    In modern English, using this word to describe mental illness is often seen as insensitive; advise students to use 'mentally ill' in serious contexts.
  2. 4 busy or chaotic (adj.)
    B1 Intermediate Informal

    very busy, fast, or full of activity.

    characterised by chaotic activity or extreme haste.

    Example

    Work has been crazy lately with the new project starting.

    Example

    The atmosphere in the newsroom became crazy as the election results started pouring in from the coastal districts.
  3. 5 extremely (adv.)
    C1 Advanced Slang American English

    very or extremely.

    used as an intensifier to mean 'to a great degree'.

    Example

    That new video game is crazy expensive.

    Example

    The traffic on the bridge was crazy slow this morning due to the construction work.
  4. 6 an eccentric person (n.)
    C1 Advanced Slang Informal

    a person who behaves in a very strange or wild way.

    a person who is perceived as insane or highly eccentric.

    Example

    Don't listen to him; he's just a crazy who shouts at cars.

    Example

    The local residents viewed the inventor as a bit of a crazy, despite his obvious technical brilliance.
Origin

From craze (“to crush”) + -y, akin to being "crazed up". Compare cracked up (“suffered a mental breakdown; be insane”), crackpot. Compare typologically Russian чо́кнутый (čóknutyj).

Word family
Idioms4 entries

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