crazy

crazy — adjective

1. doing or saying things that are very stupid and completely lacking in good sense

1.adjectiveA2
Definition

doing or saying things that are very stupid and completely lacking in good sense or reason

Example

Christopher thought it was a crazy idea to drive across the country in one day.

collocation: crazy idea

The whole plan seemed crazy because it would never survive a safety check.

subject: inanimate (plan)

Common collocations
  • crazy idea
  • crazy plan
  • crazy thing
  • crazy suggestion
Synonyms
  • stupid

    stronger and more insulting; directly attacks intelligence

  • foolish

    slightly milder; suggests bad judgment more than low intelligence

  • silly

    even milder; suggests something is trivial or childish

  • unreasonable

    focuses on lack of logical thinking rather than general foolishness

Antonyms

Grammar Patterns

crazy + noun (idea / plan / thing)

Common Mistakes

That crazy plan sounds exciting!' (when meaning it is foolish).
That crazy plan sounds foolish.
In this sense crazy means stupid or unreasonable, not cool or exciting.

2. having a serious mental illness that prevents a person from thinking clearly or

2.adjectiveB1
Definition

having a serious mental illness that prevents a person from thinking clearly or behaving in a way that society considers normal

Example

In the past, people thought that anyone acting strangely must be crazy.

historical context marker: 'in the past'

The old hospital was built to care for patients who were considered crazy.

passive: were considered crazy

Common collocations
  • go crazy
  • act crazy
  • considered crazy
  • locked away as crazy
Synonyms
  • insane

    stronger and carries a legal/clinical history; also potentially offensive

  • mentally ill

    the neutral, respectful clinical term for someone with a mental health condition

  • deranged

    more dramatic and literary; suggests severe disturbance

Antonyms
  • sane

    mentally healthy and of sound mind

  • lucid

    thinking clearly and rationally

Grammar Patterns

be crazy

go crazy

act crazy

Usage Note

This sense can be offensive when used to describe someone with an actual mental health condition. In modern usage it appears mostly in historical contexts, in quoted speech, or as an informal exaggeration ('I feel like I am going crazy with all this work'). The clinical terms 'mentally ill' or 'having a mental health condition' are preferred in serious contexts.

Common Mistakes

She is crazy and needs to see a doctor.' (offensive).
She has a mental health condition and needs professional support.
'Crazy' in a medical context sounds dismissive and insulting.

3. very annoyed or angry about a situation, especially one that feels unfair or fru

3.adjectiveB1
Definition

very annoyed or angry about a situation, especially one that feels unfair or frustrating

Example

Aarav was crazy with anger when he saw that his bicycle had been stolen.

pattern: crazy with + emotion noun

The noise from the building site is driving the neighbours crazy.

pattern: drive someone crazy

Common collocations
  • drive someone crazy
  • go crazy
  • crazy with anger
  • crazy with frustration
Synonyms
  • annoyed

    milder and more general; does not require a fixed phrase pattern

  • furious

    much stronger; suggests extreme anger

  • irritated

    slightly less intense; focuses on being bothered by something small

Antonyms
  • calm

    not angry or upset

  • patient

    able to stay calm in a frustrating situation

Grammar Patterns

drive someone crazy

go crazy

make someone crazy

Usage Note

This sense appears almost exclusively in the fixed patterns 'drive someone crazy', 'go crazy', or 'make someone crazy'. The adjective by itself ('I am crazy') does not convey anger — that reading only works inside these constructions.

Common Mistakes

I am crazy about the noise from the street.
The noise from the street is driving me crazy.
'Crazy about' means enthusiastic, not angry. Use 'drive someone crazy' for annoyance.

4. having an extremely strong interest in something or someone, so that it takes up

4.adjectiveA2
Definition

having an extremely strong interest in something or someone, so that it takes up a great deal of your time, attention, and energy

Example

Rodrigo is crazy about horse-riding and goes to the stables every weekend.

pattern: crazy about + gerund

Cyrus is crazy for video games and pre-orders every new title that comes out.

pattern: crazy for + noun

Common collocations
  • crazy about
  • crazy for
  • go crazy over
  • crazy about football
  • crazy about music
Synonyms
  • enthusiastic

    more formal and neutral; less intense

  • passionate

    similar intensity but suggests emotional depth rather than obsessive interest

  • obsessed

    stronger and more negative; suggests the interest has become unhealthy

  • mad

    British equivalent; 'mad about football' means the same as 'crazy about football'

Antonyms

Grammar Patterns

crazy about + noun/gerund

crazy for + noun

go crazy for/over + noun

Usage Note

Commonly followed by 'about' or 'for' to specify the object of enthusiasm. 'Crazy about' is more frequent in British English; 'crazy for' is more frequent in American English. The structure 'go crazy for/over' describes the moment of becoming enthusiastic.

Common Mistakes

I am crazy about to play tennis.
I am crazy about playing tennis.
'Crazy about' must be followed by a noun or a gerund (verb + -ing), not an infinitive.

5. very strange, unusual, or surprising in a way that seems hard to believe or diff

5.adjectiveB1
Definition

very strange, unusual, or surprising in a way that seems hard to believe or difficult to explain

Example

A woman on the bus wore a crazy hat shaped like a giant piece of fruit.

collocation: crazy hat

Rin told us a crazy story about meeting a famous actor at a noodle shop.

collocation: crazy story

Common collocations
  • crazy story
  • crazy hat
  • crazy colour
  • crazy outfit
  • crazy idea
Synonyms
  • bizarre

    similar in meaning but slightly more formal; suggests things are unsettlingly strange

  • weird

    very common informal alternative; slightly milder

  • ridiculous

    adds a sense of being laughable or absurd

  • absurd

    suggests something is so unreasonable it is almost funny

Antonyms
  • normal

    what is usual, typical, or expected

  • ordinary

    not unusual or special in any way

Grammar Patterns

crazy + noun (story / colour / outfit)

Idioms

like crazy/mad

idiom

Doing something with a lot of speed, effort, or intensity.

Mia ran like crazy to catch the bus this morning.

Did you see Diego painting like mad in the studio?

crazy — noun

crazy — adverb

Word family

  • crazily
    adverbB1
  • craziness
    nounB1
  • craze
    nounB2

Synonym discussion

Sense: adjective/1

All four words describe a lack of good sense, but they differ in strength and flavour. 'Stupid' is the strongest and most insulting — it suggests a permanent lack of intelligence. 'Foolish' is milder and points to bad judgment in a specific situation rather than low intelligence overall. 'Silly' is the gentlest; it suggests the action is trivial or childish rather than seriously wrong. 'Unreasonable' focuses on a failure to think logically, so it sounds more neutral and factual. For example, 'It was crazy to drive without a map' could become 'It was foolish to drive without a map' (bad judgment), 'It was silly to worry about getting lost' (trivial), or 'It was unreasonable to expect to find the way by guesswork' (lack of logic). 'Stupid' would sound harsh in most of these contexts.

stupid ↗foolish ↗silly ↗unreasonable ↗

Common collocations

Nouns

  • crazy idea
  • crazy plan
  • crazy story
  • crazy person
  • crazy behaviour

Adverbs

  • absolutely crazy
  • completely crazy
  • totally crazy
  • really crazy
  • a little crazy

Phrases

  • drive someone crazy
  • go crazy
  • like crazy
  • crazy about something

Prepositions

  • crazy about
  • crazy for
  • crazy with

Etymology

Old NorseMiddle EnglishModern English

The word 'crazy' comes from 'craze' (meaning 'to crack, to break into pieces'), which entered English from Old Norse 'krasa' ('to shatter'). In the late 1500s, something that was 'crazed' had cracks or flaws — a 'crazed' pot was a broken pot. By the 1580s, the meaning had moved from physical cracking to mental cracking: a person whose mind was 'crazed' was broken or damaged in their thinking. The informal senses — 'extremely enthusiastic' (early 1900s) and 'very' as an adverb (late 1900s) — are much newer and grew out of the idea that intense enthusiasm is like a kind of temporary madness.