Synonyms of the word

harebrained

• adj. (of an idea or plan etc) absurd, foolish or stupid.
• adj. (of a person) frivolous and silly; featherbrained or scatterbrained.

foolish

• adj. (of a person, an action, etc.) Lacking good sense or judgement; unwise.
• adj. Resembling or characteristic of a fool.

insane

• adj. Exhibiting unsoundness or disorder of mind; not sane; mad; deranged in mind; delirious; distracted.
• adj. Used by, or appropriated to, insane persons.
• adj. Causing insanity or madness.
• adj. Characterized by insanity or the utmost folly; ridiculous; unpractical.

mad

• adj. Insane; crazy, mentally deranged.
• adj. (chiefly US; UK dated + regional) Angry, annoyed.
• adj. Wildly confused or excited.
• adj. Extremely foolish or unwise; irrational; imprudent.
• adj. (colloquial, usually with for or about) Extremely enthusiastic about; crazy about; infatuated with; overcome…
• adj. (of animals) Abnormally ferocious or furious; or, rabid, affected with rabies.
• adj. (slang, chiefly Northeastern US) Intensifier, signifies an abundance or high quality of a thing; very,…
• adj. (of a compass needle) Having impaired polarity.
• adv. (slang, New England, New York and Britain, dialect) Intensifier; to a large degree; extremely; exceedingly;…
• v. (obsolete, intransitive) To be or become mad.
• v. (now colloquial US) To madden, to anger, to frustrate.