Definition of dumb adjective from the Oxford Advanced Learner's Dictionary

     

    dumb

     adjective
    adjective
    BrE BrE//dʌm//
     
    ; NAmE NAmE//dʌm//
     
    (dumber, dumbest) Stupid
     
    jump to other results
  1. 1(old-fashioned, sometimes offensive) unable to speak She was born deaf and dumb. Dumb used in this meaning is old-fashioned and can be offensive. It is better to use speech-impaired instead.
  2. 2temporarily not speaking or refusing to speak We were all struck dumb with amazement. We sat there in dumb silence.
  3. 3(informal, especially North American English) stupid That was a pretty dumb thing to do. If the police question you, act dumb (= pretend you do not know anything). In her early movies she played a dumb blonde. See related entries: Stupid
  4. Word Origin Old English, of Germanic origin; related to Old Norse dumbr and Gothic dumbs ‘mute’, also to Dutch dom ‘stupid’ and German dumm ‘stupid’.Extra examples I’m sure my question sounded really dumb. She sat there, dumb with rage. They were struck dumb by some sort of shock. They were struck dumb with amazement. Don’t be so dumb! His new girlfriend is a classic dumb blonde. How could he be so dumb as to do that? I must have sounded really dumb. If the police question you, act dumb She was born deaf and dumb. She’s going out with some dumb jock from her high school. That’s the dumbest idea I ever heard. This president is even dumber than his father. We all sat there in dumb silence. a stupid/​silly/​foolish/​dumb mistake
See the Oxford Advanced American Dictionary entry: dumb