dumb / dəm/ • adj. 1. chiefly offens. (of a person) unable to speak, most typically because of congenital deafness: he was born deaf, dumb, and blind. ∎  (of animals) unable to speak as a natural state and thus regarded as helpless or deserving pity. ∎  temporarily unable or unwilling to speak: she stood dumb while he poured out a stream of abuse. ∎  resulting in or expressed by speechlessness: they stared in dumb amazement.2. inf. stupid: a dumb question. ∎  (of a computer terminal) able only to transmit data to or receive data from a computer; having no independent processing capability. Often contrasted with intelligent.• v. [tr.] 1. (dumb something down) inf. simplify or reduce the intellectual content of something so as to make it accessible to a larger number of people: critics have accused publishers of dumbing down books. ∎  [intr.] (dumb down) become less intellectually challenging: the need to dumb down for mass audiences.2. poetic/lit. make dumb or unheard; silence: a splendor that dazed the mind and dumbed the tongue.DERIVATIVES: dumb·ly adv.dumb·ness n.

dumb dumb blonde a blonde-haired woman perceived in a stereotypical way as being attractive but unintelligent (compare blonde moment).
the dumb ox a nickname for St Thomas Aquinas; according to Butler's Lives of the Saints (1756) given to him by his schoolfellows because they thought his habitual silence indicated stupidity.

dumb destitute of speech, mute. OE. dumb = OS. dumb (Du. dom) stupid OHG. tump stupid, deaf (G. dumm stupid), ON. dumbr, Goth. dumbs mute; of unkn. orig.