This informal meaning describes an action, idea, or person considered unintelligent or poorly judged and may sound insulting.
That was a dumb mistake.
I felt dumb for forgetting the key.
This dated meaning refers to an inability to speak and is now widely considered offensive when applied to people.
The old text described the character as deaf and dumb.
Modern usage avoids calling a person dumb because they cannot speak.
This literary meaning describes a person becoming silent because of strong emotion.
The announcement left everyone dumb with surprise.
He stood dumb with fear.
In technology, dumb describes equipment with little or no independent processing or decision-making ability.
The system uses a dumb terminal.
A dumb device relies on a central computer.
Usually used as dumb down, this meaning refers to simplifying content, often excessively.
Do not dumb down the explanation too much.
The editor dumbed down the technical article.
