insane
[adjective]
Synonyms:
- mad, crazed, crazy, demented, deranged, mentally ill, out of one's mind, unhinged
- stupid, daft (informal), foolish, idiotic, impractical, irrational, irresponsible, preposterous, senseless

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Antonyms: sane
Contrasted words: judicious, sapient, sensible, wise, rational, reasonable, balanced, logical, subtle, healthy, sound, clear, lucid, feasible, possible, practicable, usable, sane, practical, realistic
Related Idioms: around the bend, crazy as a coot, not all there, not right in one's head, off one's dot, off one's nut (or rocker), off one's onion, out of (or off) one's head, out of one's mind, touched in the head
Related Words: irrational, unreasonable, bewildered, distracted, dotty, eccentric, off, rocky, strange, touched, dippy, fanciful, fantastic, imaginary, visionary, impractical, unrealistic

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English Thesaurus: crazy, mad, nuts, loony, insane, ...

[TahlilGaran] English Synonym Dictionary ▲

in‧sane /ɪnˈseɪn/ adjective

1. informal completely stupid or crazy, often in a way that is dangerous:
That’s an insane risk.
The whole idea sounds absolutely insane to me.
Why did you do that? Have you gone insane?

2. someone who is insane is permanently and seriously mentally ill so that they cannot live in normal society:
The killer was declared criminally insane.

3. the insane people who are mentally ill:
a hospital for the insane

4. drive somebody insane informal to make someone feel more and more annoyed or angry, usually over a long period of time Synonym : drive somebody mad:
My little brother’s been driving me insane all weekend.
—insanely adverb:
insanely jealous
She giggled insanely.

[TahlilGaran] Dictionary of Contemporary English ▲

insane
adj.
I. mentally ill/crazy
VERBS be, look | become, go He later became insane and was confined to an asylum. He went almost insane when he heard that his daughter had died.
drive sb You're driving me nearly insane with that noise.
certify sb, declare sb In 1975 she was certified clinically insane and sent to a mental hospital.
ADV. completely, totally | almost, nearly | a little | dangerously | clinically | criminally He is criminally insane, unable to stop himself attacking women.

[TahlilGaran] Collocations Dictionary ▲

insane
II. very stupid/dangerous
VERBS be, seem It seems insane to cut the budget now.
ADV. quite, totally The whole idea is quite insane.

[TahlilGaran] Collocations Dictionary ▲

crazy very strange or not sensible – used about people, ideas, and behaviour:
People think I’m crazy when I start talking about ghosts.
It was a crazy thing to do.
mad British English crazy:
Are you mad?
Whose mad idea was that?
At first, everyone thought he was completely mad.
nuts informal (also bonkers British English) [not before noun] crazy:
The whole thing sounds completely nuts.
Have you gone bonkers?
loony informal crazy:
another loony suggestion
The man is totally loony.
insane completely crazy:
I know it sounds insane, but it’s true.

[TahlilGaran] English Thesaurus ▲

mentally ill having an illness that affects your mind and your behaviour:
Many mentally ill people are treated in the community.
He was declared mentally ill and unfit to stand trial.
crazy informal mentally ill:
I couldn’t think straight. I felt like I was going crazy (=becoming crazy).
mad old-fashioned mentally ill. This word is now usually considered offensive, and is usually used in a different meaning, when you think that someone's ideas are not sensible:
Swift himself went mad (=became mad) later in life.
a mad old woman
insane [not before noun] old-fashioned having a serious and permanent mental illness:
She went insane after her two young sons were murdered.
a hospital for the criminally insane
disturbed not behaving in a normal way because of mental or emotional problems, especially problems that are caused by bad experiences:
She teaches emotionally disturbed children.
Her experiences left her deeply disturbed.
unstable having an emotional state that often changes very suddenly:
Her mother was mentally unstable.
He lived in a small Putney flat with his ageing Aunt Bunny, and his emotionally unstable sister, Nancy.
He was too unstable to be a leader.
deranged behaving in a crazy or dangerous way, usually because of being mentally ill:
A deranged young woman entered the school and took the life of one young boy.
psychopathic having a serious and permanent mental illness that causes violent or criminal behaviour:
The film is about a psychopathic killer.
psychotic suffering from or caused by a serious mental illness that changes your character and makes you unable to behave in a normal way:
psychiatric services for chronic psychotic patients.
There is a tendency for psychotic illnesses to be inherited.
neurotic relating to or suffering from a mental illness that makes you unreasonably worried of frightened:
His mother was neurotic and insecure.
She's neurotic about her weight.
A bored or lonely horse may become so neurotic that it chases itself around in circles.

[TahlilGaran] English Thesaurus ▲