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adjective \ˈdəl\

Simple Definition of dull

  • : not exciting or interesting

  • : having an edge or point that is not sharp

  • of a sound : not clear and loud

Source: Merriam-Webster's Learner's Dictionary

Full Definition of dull

  1. 1 :  mentally slow :  stupid

  2. 2 a :  slow in perception or sensibility :  insensible <somewhat dull of hearing> b :  lacking zest or vivacity :  listless <a dull performance>

  3. 3 :  slow in action :  sluggish

  4. 4 a :  lacking in force, intensity, or sharpness <a dull ache> b :  not resonant or ringing <a dull booming sound>

  5. 5 :  lacking sharpness of edge or point <a dull knife>

  6. 6 :  lacking brilliance or luster <a dull finish>

  7. 7 of a color :  low in saturation and low in lightness

  8. 8 :  cloudy <dull weather>

  9. 9 :  tedious, uninteresting <dull lectures>

dullness also dulness play \ˈdəl-nəs\ noun
dully play \ˈdə(l)-lē\ adverb

Examples of dull in a sentence

  1. the dull roar of the crowd

  2. <the dull knife just bounced off the skin of the tomato without cutting it>

Origin of dull

Middle English dul; akin to Old English dol foolish, Old Irish dall blind

First Known Use: 13th century

Synonym Discussion of dull

dull, blunt, obtuse mean not sharp, keen, or acute. dull suggests a lack or loss of keenness, zest, or pungency <a dull pain> <a dull mind>. blunt suggests an inherent lack of sharpness or quickness of feeling or perception <a person of blunt sensibility>. obtuse implies such bluntness as makes one insensitive in perception or imagination <too obtuse to take the hint>.

synonyms see in addition stupid

Rhymes with dull




Simple Definition of dull

  • : to become or cause (something) to become less clear, distinct, bright, or shiny

  • : to make (something, such as a feeling) less sharp, strong, or severe

  • : to become or cause (something, such as a knife or blade) to become less sharp

Source: Merriam-Webster's Learner's Dictionary

Full Definition of dull

  1. transitive verb
  2. :  to make dull <dull a knife's edge>

  3. intransitive verb
  4. :  to become dull

Examples of dull in a sentence

  1. Fog dulled the morning sunlight.

  2. Special earplugs dulled the sound of the chain saw.

  3. His hair dulled as he aged.

  4. The dog's eyes dulled as he got sick.

  5. She takes medicine to dull the pain.

  6. Fear dulled his need for adventure.

  7. The knife was dulled from use.

  8. The blade should be replaced as soon as it dulls.

13th Century

First Known Use of dull

13th century

DULL Defined for Kids



adjective \ˈdəl\

Definition of dull for Students


  1. 1 :  not sharp in edge or point :  blunt <a dull knife>

  2. 2 :  not shiny or bright <The old trophy had a dull finish.>

  3. 3 :  not interesting :  boring <a dull movie>

  4. 4 :  not clear and ringing <a dull sound>

  5. 5 :  not sharp or intense <I have a dull ache in my arm.>

  6. 6 :  slightly grayish <a dull red>

  7. 7 :  cloudy 1, overcast <a dull sky>

  8. 8 :  slow in understanding things :  not smart

  9. 9 :  without energy or spirit <She was feeling dull.>

  10. 10 :  slow in action :  sluggish <Business was dull.>

dullness noun
dully adverb




Definition of dull for Students


  1. :  to make or become less sharp, bright, or intense <Medicine dulled the pain.>

Medical Dictionary


adjective \ˈdəl\

Medical Definition of dull

  1. 1:  mentally slow or stupid

  2. 2:  slow in perception or sensibility

  3. 3:  lacking sharpness of edge or point <a dull scalpel>

  4. 4:  lacking in force, intensity, or acuteness <a dull pain>

dull verb
dullness or dulness \ˈdəl-nəs\play noun
dully \ˈdəl-ē\play adverb

Seen and Heard

What made you want to look up dull? Please tell us where you read or heard it (including the quote, if possible).


to dishevel or rumple

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