crazy

Adjective

• intensely enthusiastic about or preoccupied with
  • crazy about cars and racing
    
  • he is potty about her
    

• bizarre or fantastic
  • had a crazy dream
    
  • wore a crazy hat
    

• possessed by inordinate excitement
  • the crowd went crazy
    
  • was crazy to try his new bicycle
    

• foolish; totally unsound
  • a crazy scheme
    
  • half-baked ideas
    
  • a screwball proposal without a prayer of working
    

• affected with madness or insanity
  • a man who had gone mad
    

Noun

• someone deranged and possibly dangerous

Related words

• Synonyms: 
  wild , dotty , gaga , half-baked , screwball , softheaded , brainsick , demented , disturbed , mad , sick , unbalanced , unhinged , loony , looney , nutcase , weirdo