The word(s) "dumb" appears 7 time(s) in 7 verse(s) in Quran in Muhammad Pickthal translation.

(1) Deaf, dumb and blind; and they return not.

(2) The likeness of those who disbelieve (in relation to the messenger) is as the likeness of one who calleth unto that which heareth naught except a shout and cry. Deaf, dumb, blind, therefore they have no sense.

(3) Those who deny Our revelations are deaf and dumb in darkness. Whom Allah will sendeth astray, and whom He will He placeth on a straight path.

(4) Then, when they forgot that whereof they had been reminded, We opened unto them the gates of all things till, even as they were rejoicing in that which they were given, We seized them unawares, and lo! they were dumbfounded.

(5) Lo! the worst of beasts in Allah's sight are the deaf, the dumb, who have no sense.

(6) And Allah coineth a similitude: Two men, one of them dumb, having control of nothing, and he is a burden on his owner; whithersoever he directeth him to go, he bringeth no good. Is he equal with one who enjoineth justice and followeth a straight path (of conduct)?

(7) And he whom Allah guideth, he is led aright; while, as for him whom He sendeth astray, for them thou wilt find no protecting friends beside Him, and We shall assemble them on the Day of Resurrection on their faces, blind, dumb and deaf; their habitation will be hell; whenever it abateth, We increase the flame for them.