Synonyms of the word 
CRACKBRAINED → IDIOTIC - INSANE
crackbrained
- adj. Idiotic.
idiotic
- adj. Pertaining to or resembling an idiot; afflicted with idiocy.
- adj. Having the quality of idiocy; very foolish; stupid; nonsensical.
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.
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