Synonyms of the word

dumbness

• n. The state of being dumb or mute: that is, of not communicating vocally, whether from selective mutism…
• n. Muteness, silence; abstention from speech.
• n. Show or gesture without words; pantomime; dumb-show.
• n. (informal) The quality of being stupid or foolish.

denseness

• n. The quality of being dense, especially in the sense of limited mental capacity.

slow-wittedness

• n. The state of being slow-witted.

stupidity

• n. (uncountable) The property of being stupid.
• n. (countable) An act that is stupid.