What a dumb question.
a bunch of dumb kids
'What is it?' I asked, playing dumb (=pretending to be stupid).
She's no dumb blonde (=a pretty woman with blonde hair who seems stupid).
unable to speak, because you are angry, surprised, shocked etc:
He stared at the burnt-out car in dumb disbelief.
She was struck dumb with terror.
someone who is dumb is not able to speak at all. Many people think that this use is offensive [↪ mute]
➔ deaf and dumbat deaf (1)
something good that happens in an unexpected way, especially when it is not deserved:
It was just dumb luck that we found the place at all.
used to talk about animals when you want to emphasize that humans often treat them badly and they cannot protect themselves
For a few seconds she gazed dumbly at him.
—dumbness noun [uncountable]