Dumb adj. 1.Destitute of the power of speech; unable; to utter articulate sounds; as, the dumb brutes. "To unloose the very tongues even of dumb creatures."
2.Not willing to speak; mute; silent; not speaking; not accompanied by words; as, dumb show. "This spirit, dumb to us, will speak to him." "To pierce into the dumb past."
3.Lacking brightness or clearness, as a color. (R.) "Her stern was painted of a dumb white or dun color."
4.Lacking intelligence; having poor judgment; stupid; dull-witted; of persons.
5.Exhibiting poor judgment or lack of wisdom; leading predictably to unfavorable consequences; of actions.
Deaf and dumb. See Deaf-mute. Dumb ague, or Dumb chill, a form of intermittent fever which has no well-defined "chill." (U.S.)
Dumb animal, any animal except man; usually restricted to a domestic quadruped; so called in contradistinction to man, who is a "speaking animal."
Dumb cake, a cake made in silence by girls on St. Mark's eve, with certain mystic ceremonies, to discover their future husbands.
Dumb cane (Bot.), a west Indian plant of the Arum family (Dieffenbachia seguina), which, when chewed, causes the tongue to swell, and destroys temporarily the power of speech.
Dumb crambo. See under crambo. Dumb show. (a)Formerly, a part of a dramatic representation, shown in pantomime. "Inexplicable dumb shows and noise."
(b)Signs and gestures without words; as, to tell a story in dumb show.
To strike dumb, to confound; to astonish; to render silent by astonishment; or, it may be, to deprive of the power of speech.
Synonyms: Silent; speechless; noiseless. See Mute. 
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