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  1. ホーム /
  2. 辞書 /
  3. English Dictionary /
  4. crazy

crazy

/ˈkreɪzi/
mentally ill or irrational

She was acting crazy after drinking too much coffee.

She was behaving in an irrational or wild manner.


formal

mentally ill or affected by a mental disorder

The doctor diagnosed him as crazy after years of erratic behavior.

The doctor determined he had a serious mental illness.

This is the most formal and clinical usage of the word.

informal

extremely foolish or irrational

It's crazy to drive so fast in this weather!

It's extremely foolish to drive so fast in bad weather.

Common in everyday speech to describe reckless or illogical behavior.

informal

very enthusiastic or passionate

She's crazy about her new puppy.

She is very excited and passionate about her new puppy.

Often used to describe strong positive emotions.

Collocations

crazy aboutvery enthusiastic aboutgo crazybecome very excited or upsetcrazy ideaa foolish or irrational plan

Synonyms

insanemadirrationalwildunhinged

Antonyms

sanerationalcalmsensible

Related Phrases

go crazyphrasal verb
to become very excited or upset
crazy in lovephrase
extremely passionate about someone

Pro Tip

Context Matters

The meaning of 'crazy' can change dramatically based on context. Pay attention to the tone and situation to understand whether it's being used positively or negatively.

Gold Rule

Avoid in Formal Settings

When referring to mental illness, use more formal terms like 'mentally ill' or 'affected by a mental disorder' in professional or clinical contexts.

Word Origin

From Middle English 'crasy', from Old French 'crasie', from Latin 'crasis', meaning 'mixture', from Greek 'krasis', meaning 'mixture'. Originally referred to a mixture of good and bad qualities, later used to describe mental instability.

Usage Notes

The word 'crazy' is highly versatile and can be used in both positive and negative contexts. It is commonly used in informal speech but can be considered offensive in formal or clinical settings when referring to mental illness.

Word Breakdown

cra
possibly from Latin 'crasis' (mixture)
root
+
-zy
possibly influenced by 'manic' or 'maniac'
suffix
English Dictionary
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