stupid

/ˈstuːpɪd/
adjective
  1. Lacking intelligence or common sense; not smart.
    • Don't be stupid; you should wear a helmet when biking.
    • It was a stupid mistake to leave the keys in the car.
    • He felt stupid after forgetting his own phone number.
  2. Causing annoyance or frustration; silly or foolish.
    • The movie had a stupid plot that made no sense.
    • Why did you buy that stupid hat?
    • I can't get this stupid computer to work.
  3. In a state of being dazed or unable to think clearly.
    • She was stupid with exhaustion after the long hike.
    • The loud noise left him stupid and confused.
    • He stared stupidly at the broken vase, not knowing what to say.
noun
  1. A person who is not intelligent or who acts foolishly.
    • He called me a stupid for asking a simple question.
    • Only a stupid would try to cross the river during a flood.
    • Don't be such a stupid; read the instructions first.