Definitions
01strange or wild
A2 · Elementary Informal
adj. very strange, unusual, or foolish.
adj. not sensible or logical; extremely foolish or strange.
“It was a crazy idea to drive through the storm at night.”
“The plan to launch the product without any prior testing seemed crazy to the rest of the board members.”
Synonyms
02very enthusiastic
A2 · Elementary Informal
adj. liking something or someone very much.
adj. extremely enthusiastic or fond of a particular person, activity, or object.
“My brother is crazy about football and never misses a game.”
“She has been crazy about jazz since she was a teenager, spending most of her weekends at local clubs.”
Synonyms
Antonyms
03mentally ill
B1 · Intermediate Informal
adj. having a mind that does not work in a normal way.
adj. suffering from a mental illness or being of unsound mind.
“The old stories say a crazy man used to live in that house.”
“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.
Teaching 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.
Antonyms
04busy or chaotic
B1 · Intermediate Informal
adj. very busy, fast, or full of activity.
adj. characterised by chaotic activity or extreme haste.
“Work has been crazy lately with the new project starting.”
“The atmosphere in the newsroom became crazy as the election results started pouring in from the coastal districts.”
05extremely
C1 · Advanced Slang · American English
adv. very or extremely.
adv. used as an intensifier to mean 'to a great degree'.
“That new video game is crazy expensive.”
“The traffic on the bridge was crazy slow this morning due to the construction work.”
Synonyms
06an eccentric person
C1 · Advanced Countable noun Slang · Informal
n. a person who behaves in a very strange or wild way.
n. a person who is perceived as insane or highly eccentric.
“Don't listen to him; he's just a crazy who shouts at cars.”
“The local residents viewed the inventor as a bit of a crazy, despite his obvious technical brilliance.”
Synonyms
Real-World Examples
“The crazy plan to explode a nuclear bomb on the Moon.” “Dreamed up by Dominic Cummings to fund “crazy” ideas, the Advanced Research and Invention Agency (Aria) is meant to “restore Britain’s place as a scientific superpower”.” “In our crazy, unregulated world, we watch the unedifying spectacle of two rogue nations, each awash with nuclear weapons, going to war to stop a third rogue nation from acquiring similar weaponry.” Etymology
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).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
NOUN
ADJECTIVE
Idioms
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.A2 KeyIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.3.0–4.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 2.0–2.524–43TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.225–549
- Frequency
- Very common
- Level
- A2 · ElementaryOxford
- Updated
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QR code
englishreference.com/q/crazy
「カタカナ語」 data: JMdict (EDRDG), CC BY-SA 4.0