dumb
1. [ adjective ] slow to learn or understand; lacking intellectual acuity
Synonyms: slow dull obtuse dim dense
Examples:

"so dense he never understands anything I say to him" "never met anyone quite so dim" "although dull at classical learning, at mathematics he was uncommonly quick"- Thackeray "dumb officials"

Related terms: stupid
2. [ adjective ] lacking the power of human speech
Examples:

"dumb animals"

Related terms: inarticulate
3. [ adjective ] unable to speak temporarily
Synonyms: speechless
Examples:

"struck dumb" "speechless with shock"

Related terms: inarticulate
4. [ adjective ] unable to speak because of hereditary deafness
Synonyms: silent mute
Related terms: inarticulate
Similar spelling:   dump