crack-brained

A man with a crack-brained idea tries to build a flying machine from umbrellas.

Definition

Adjective: - Foolish or insane: "crack-brained" describes someone or something that is extremely foolish, irrational, or lacking common sense, often to the point of appearing mentally unstable.

Usage Examples

• (Describing an idea as foolish and impractical.)
• (Calling the theory irrational or nonsensical.)
• (Describing a person as foolish or insane.)

Advanced Usage

• "crack-brained idea": a plan or concept that is obviously absurd or impractical.
  • The crack-brained idea of swimming across the Atlantic Ocean was met with laughter. (An idea that is clearly ridiculous.)
• "crack-brained rant": a speech or outburst that is incoherent or irrational.
  • His crack-brained rant about the government controlling the weather confused everyone. (A foolish and illogical speech.)

Variants and Related Words

• Crackpot (noun/adjective): a person with eccentric or foolish ideas; similar in meaning to "crack-brained."
  • He is a crackpot who believes in perpetual motion machines. (A foolish or eccentric person.)
• Cracked (adjective): mentally unbalanced or eccentric; less severe than "crack-brained."
  • She gave a cracked laugh at the absurdity of the situation. (A slightly unbalanced reaction.)

Synonyms

• Foolish: lacking good sense or judgment.
• Insane: in a state of mind that prevents normal perception, behavior, or social interaction; often used hyperbolically.
• Absurd: wildly unreasonable, illogical, or inappropriate.
• Daft: silly or foolish (informal, British English).

Related Idioms

• "Out of one's mind": to be irrational or insane.
  • You must be out of your mind to try that crack-brained stunt. (You are acting foolishly or insanely.)
• "Have a screw loose": to be slightly eccentric or foolish.
  • Anyone who believes that conspiracy theory has a screw loose. (Is slightly foolish or irrational.)