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verb \ˈdau̇t\

Simple Definition of doubt

  • : to be uncertain about (something) : to believe that (something) may not be true or is unlikely

  • : to have no confidence in (someone or something)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of doubt

  1. transitive verb
  2. 1 archaic a :  fear b :  suspect

  3. 2 :  to be in doubt about <he doubts everyone's word>

  4. 3 a :  to lack confidence in :  distrust <find myself doubting him even when I know that he is honest — H. L. Mencken> b :  to consider unlikely <I doubt if I can go>

  5. intransitive verb
  6. :  to be uncertain

doubtable play \ˈdau̇-tə-bəl\ adjective
doubter noun
doubtingly play \-tiŋ-lē\ adverb

Examples of doubt in a sentence

  1. I have always doubted the existence of life on other planets.

  2. No one doubts that the mission will be a success.

  3. I seriously doubt my parents will let me go.

  4. Do you think you can come tonight? I doubt it.

  5. She doubted his ability to succeed.

  6. He said he could do it, but I couldn't help doubting him.

Origin of doubt

Middle English douten, from Anglo-French duter, douter, from Latin dubitare to be in doubt; akin to Latin dubius dubious

First Known Use: 13th century




Simple Definition of doubt

  • : a feeling of being uncertain or unsure about something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of doubt

  1. 1 a :  uncertainty of belief or opinion that often interferes with decision-making b :  a deliberate suspension of judgment

  2. 2 :  a state of affairs giving rise to uncertainty, hesitation, or suspense <the outcome is still in doubt>

  3. 3 a :  a lack of confidence :  distrust <has doubts about his abilities> b :  an inclination not to believe or accept <a claim met with doubt>

no doubt

Examples of doubt in a sentence

  1. I still have moments of doubt.

  2. There can be little doubt that smoking is bad for your health.

  3. I had a nagging doubt in the back of my mind.

13th Century

First Known Use of doubt

13th century

Synonym Discussion of doubt

uncertainty, doubt, dubiety, skepticism, suspicion, mistrust mean lack of sureness about someone or something. uncertainty may range from a falling short of certainty to an almost complete lack of conviction or knowledge especially about an outcome or result <assumed the role of manager without hesitation or uncertainty>. doubt suggests both uncertainty and inability to make a decision <plagued by doubts as to what to do>. dubiety stresses a wavering between conclusions <felt some dubiety about its practicality>. skepticism implies unwillingness to believe without conclusive evidence <an economic forecast greeted with skepticism>. suspicion stresses lack of faith in the truth, reality, fairness, or reliability of something or someone <regarded the stranger with suspicion>. mistrust implies a genuine doubt based upon suspicion <had a great mistrust of doctors>.

DOUBT Defined for Kids



verb \ˈdau̇t\

Definition of doubt for Students


  1. 1 :  to be uncertain about <I doubt he's right.>

  2. 2 :  to lack confidence in <I doubted my own judgment.>

  3. 3 :  to consider unlikely <I doubt I can go tonight.>




Definition of doubt for Students

  1. 1 :  a feeling of being uncertain <Their predicament filled her with doubt.>

  2. 2 :  a reason for disbelief <There can be no doubt that you have a most unusual pig. — E. B. White, Charlotte's Web>

  3. 3 :  the condition of being undecided <Our plans are now in doubt.>

  4. 4 :  a lack of trust <I have my doubts about this explanation.>

Seen and Heard

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tending to dismiss important matters

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