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Synonyms

uncertain

American  
[uhn-sur-tn] / ʌnˈsɜr tn /

adjective

  1. not definitely ascertainable or fixed, as in time of occurrence, number, dimensions, or quality.

    Synonyms:
    unpredictable, unsure
  2. not confident, assured, or free from hesitancy.

    an uncertain smile.

  3. not clearly or precisely determined; indefinite; unknown.

    a manuscript of uncertain origin.

    Synonyms:
    undetermined, unsettled
  4. vague; indistinct; not perfectly apprehended.

    an abstruse novel with uncertain themes.

  5. subject to change; variable; capricious; unstable.

    a person of uncertain opinions.

  6. ambiguous; unreliable; undependable.

    Her loyalties are uncertain.

  7. dependent on chance or unpredictable factors; doubtful; of unforeseeable outcome or effect.

  8. unsteady or flickering, as light; of changing intensity or quality.

    Synonyms:
    irregular

uncertain British  
/ ʌnˈsɜːtən /

adjective

  1. not able to be accurately known or predicted

    the issue is uncertain

  2. not sure or confident (about)

    a man of uncertain opinion

  3. not precisely determined, established, or decided

    uncertain plans

  4. not to be depended upon; unreliable

    an uncertain vote

  5. liable to variation; changeable

    the weather is uncertain

    1. unambiguously

    2. forcefully

"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

uncertain Idioms  

Related Words

Uncertain, insecure, precarious imply a lack of predictability. That which is uncertain is doubtful or problematical; it often involves danger through an inability to predict or to place confidence in the unknown: The time of his arrival is uncertain. That which is insecure is not firm, stable, reliable, or safe, and hence is likely to give way, fail, or be overcome: an insecure foundation, footing, protection. Precarious suggests great susceptibility to failure, or exposure to imminent danger: a precarious means of existence.

Other Word Forms

  • uncertainly adverb
  • uncertainness noun

Etymology

Origin of uncertain

First recorded in 1250–1300; Middle English; un- 1 + certain

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.

But he said on air that he was “told in no uncertain terms by our network’s lawyers, who called us directly, that we could not have him on the broadcast.”

From Los Angeles Times

“We were told in no uncertain terms by our network’s lawyers, who called us directly, that we could not have him on the broadcast,” Colbert said in a scathing 6½-minute monologue.

From The Wall Street Journal

Although we knew oncRNAs could be detected in blood, it was uncertain whether they would provide meaningful information in real patient samples.

From Science Daily

“Given the rapid progress of AI technology, recent investor conversations have focused on the challenge of translating near-term profit strength to uncertain long-term growth outlooks,” the Goldman teams adds.

From MarketWatch

Old-school dividend payers with lots of physical assets are back in fashion in today’s uncertain environment.

From The Wall Street Journal