idiotic

Adjective

• having a mental age of three to seven years

• incongruous; inviting ridicule
  • the absurd excuse that the dog ate his homework
    
  • that's a cockeyed idea
    
  • ask a nonsensical question and get a nonsensical answer
    
  • a contribution so small as to be laughable
    
  • it is ludicrous to call a cottage a mansion
    
  • a preposterous attempt to turn back the pages of history
    
  • her conceited assumption of universal interest in her rather dull children was ridiculous
    

• insanely irresponsible
  • an idiotic idea
    

Related words

• Synonyms: 
  imbecile , imbecilic , absurd , cockeyed , derisory , laughable , ludicrous , nonsensical , preposterous , ridiculous , crackbrained