dumb

American  

[duhm] / dʌm /

adjective

• dumber,
  comparative
• dumbest
  superlative

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.

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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

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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

Derived Forms

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

Inflected Forms

Adjectives

• dumber
  comparative
• dumbest
  superlative

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

Explanation

Today, most of the time someone or something is described as dumb when it shows a lack of thought, like your dumb idea of wearing flip-flops in a snowstorm. Dumb is the Old English word that means "mute, speechless," and itself came from an even older word dheubh meaning "confusion, stupefaction, dizziness." Today, dumb still means "unable to speak," but it doesn't have anything to do with intelligence. Its other meaning, however, does. If you make a dumb mistake, it's something you could have avoided if you thought it through first.

Example Sentences

See Examples For:

dumb dumber dumbest

But dumb isn’t the condemnation that remark deserved.

From The Wall Street Journal ● Aug. 31, 2026

"I'm not offended by all the dumb blonde jokes because I know I'm not dumb - and I'm not blonde either."

From BBC ● Aug. 26, 2026

Even as propaganda, it was pretty dumb — never discounting for currency fluctuation, alternative sourcing or domestic capacity increases, to name a few counterindicators.

From MarketWatch ● Aug. 22, 2026

Not the joke, which was dumb the way 15-year-olds are dumb.

From Slate ● Aug. 21, 2026

What are the odds that people will make smart decisions about money if they don’t need to make smart decisions—if they can get rich making dumb decisions?

From "The Big Short" by Michael Lewis

Advertising student Catalina Cruz, 19, thinks AI is "making us dumber" because "people aren't able to think for themselves any more".

From Barron's ● Sep. 15, 2026

Heath, for one, thinks docking would make fine TV: “I’ve seen a lot of dumber stuff…. We’ve got to be more exciting than lawn-mower races.”

From The Wall Street Journal ● Aug. 21, 2026

My anxiety about A.I. is not that it will make my job obsolete but that it will make me a little dumber.

From Slate ● May 24, 2026

It’s something much bigger than that, much dumber and much worse.

From Salon ● Dec. 7, 2025

It was bad enough having to come to this broken-down old school but to be behind—to seem dumber than the rest of the kids—to have to appear a fool in front of.

From "The Great Gilly Hopkins" by Katherine Paterson

Rahmani said in his opinion, Davis would "go down as one of the world's dumbest criminals", who likely would have never have faced charges if he had stayed silent.

From BBC ● Sep. 1, 2026

Collectively, they stand as a blunt reminder that war, the dumbest and most vicious human invention, occurs in time and space.

From Salon ● Jul. 4, 2026

The dumbest phrase in military history is Adolf Hitler saying “Let’s attack Russia in the winter.”

From Slate ● Jun. 24, 2026

Siri is one of the dumbest chatbots on the market.

From The Wall Street Journal ● Jun. 5, 2026

Which made her feel like the dumbest, weakest girl.

From "Eleanor & Park" by Rainbow Rowell

Related Words

• dull
• foolish