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Synonyms

dumb

American  
[duhm] / dʌm /

adjective

dumber, dumbest
  1. lacking intelligence or good judgment; stupid; dull-witted.

  2. lacking the power of speech (offensive when applied to humans).

    a dumb animal.

  3. temporarily unable to speak.

    dumb with astonishment.

  4. refraining from any or much speech; silent.

  5. made, done, etc., without speech.

  6. lacking some usual property, characteristic, etc.

  7. performed in pantomime; mimed.

  8. Computers. pertaining to the inability to do processing locally.

    A dumb terminal can input, output, and display data, but cannot process it.

  9. Nautical.

    1. (of a barge) without means of propulsion.

    2. (of any craft) without means of propulsion, steering, or signaling.


verb phrase

  1. dumb down to make or become less intellectual, simpler, or less sophisticated.

    to dumb down a textbook; American movies have dumbed down.

dumb British  
/ dʌm /

adjective

  1. lacking the power to speak, either because of defects in the vocal organs or because of hereditary deafness

  2. lacking the power of human speech

    dumb animals

  3. temporarily lacking or bereft of the power to speak

    struck dumb

  4. refraining from speech; uncommunicative

  5. producing no sound; silent

    a dumb piano

  6. made, done, or performed without speech

  7. informal

    1. slow to understand; dim-witted

    2. foolish; stupid See also dumb down

  8. (of a projectile or bomb) not guided to its target

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Sensitive Note

Dumb in the sense “lacking the power of speech” is perceived as insulting when describing humans (but not animals), probably because dumb also means “stupid; dull-witted.” The noun dummy in the sense “person who lacks the power of speech” is also perceived as insulting, as are the terms deaf-and-dumb, deaf-mute, and mute. The adjective hard of hearing is acceptable though not the term of choice, partly because it lacks directness. The preferred term is deaf, which makes no reference to an inability to speak or communicate; the capitalized word Deaf signals membership in this community.

Other Word Forms

  • dumbly adverb
  • dumbness noun
  • quasi-dumb adjective
  • quasi-dumbly adverb

Etymology

Origin of dumb

First recorded before 1000; Old English; cognate with Old Norse dumbr, Gothic dumbs, Old Saxon dumb, Old High German tump, German dumm

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“The Sun is an enormous, free fusion reactor in the sky. It is super dumb to make tiny fusion reactors on Earth.”

From The Wall Street Journal

I know this is a move that will probably come back to haunt me, but somewhere inside my dumb brain I have strong feelings about fairness.

From Literature

All based on a theory that European citizens are too dumb to take the things they read on X or elsewhere online with a grain of salt.

From The Wall Street Journal

A June study from MIT Media Lab suggests that using ChatGPT to write essays results in “cognitive debt,” a fancy way to say that artificial intelligence makes you dumb.

From The Wall Street Journal

“Business leaders aren’t dumb. They understand the Fed is not 100% independent of the government,” says Robert Wright, a professor and economic historian at the University of Austin.

From The Wall Street Journal