stupid stupid /ˈstuːpɪd/

adjective

1. () Lacking or marked by lack of intellectual acuity  ( stupid )
   lacking or marked by lack of intellectual acuity
     He made a stupid mistake that cost him the game.
   He made a stupid mistake that cost him the game.
   
2. () In a state of mental numbness especially as resulting from shock  ( stunned , stupefied , stupid , dazed )
   in a state of mental numbness especially as resulting from shock
    He had a dazed expression on his face
   he had a dazed expression on his face
    Lay semiconscious, stunned (or stupefied) by the blow
   lay semiconscious, stunned (or stupefied) by the blow
    Was stupid from fatigue
   was stupid from fatigue
   
3. Lacking intelligence  ( stupid , unintelligent )
   lacking intelligence
    A dull job with lazy and unintelligent co-workers
   a dull job with lazy and unintelligent co-workers
   

noun

1. () A person who is not very bright  ( dolt [Informal] , pillock [Informal, British] , poor fish , dullard , pudden-head [Informal, American] , pudding head [Informal] , stupe [Informal, N. American] , stupid , stupid person )
   a person who is not very bright
    The economy, stupid!
   The economy, stupid!