un·​cer·​tain·​ty | \ˌən-ˈsər-tᵊn-tē \

Definition of uncertainty 

1 : the quality or state of being uncertain : doubt

2 : something that is uncertain

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Choose the Right Synonym for uncertainty

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

Examples of uncertainty in a Sentence

There is some uncertainty about the company's future. He accepted the position without hesitation or uncertainty.

Recent Examples on the Web

Especially in a field with as much uncertainty as animal advocacy, our understanding of the best options next year might look very different from our understanding of the best options today. Kelsey Piper, Vox, "Where will your donations do the most for animals?," 27 Nov. 2018 With uncertainty surrounding raw material costs, selling prices and foreign demand, strategic planning becomes impossible. John Schmid, Milwaukee Journal Sentinel, "Trump's global trade war expected to inflict economic causalities in Wisconsin and across nation," 10 July 2018 Even worse, having years of uncertainty because of a long legal battle between states and the federal government is in no one’s best interest. WSJ, "U.S. Can Lead in EVs or Give Lead to China," 20 Nov. 2018 The repetitive nature of lifting also satisfies my need for predictability, as uncertainty fuels my anxiety. Melissa Pandika, SELF, "Lifting Heavy Weights Is My Favorite Way to Help Manage My Anxiety," 16 Nov. 2018 But inside the skylit studio on 18th Street, the message on repeat is empowerment, not uncertainty. Laura Regensdorf, Vogue, "At 35, I Went to a Millennial Egg-Freezing Clinic—and Now I’m Rethinking My Future," 12 Nov. 2018 In an email interview with me, Bradford mentioned uncertainty as a pervasive factor. Vanessa Willhoughby, Allure, "The Reality of Navigating the Mental Health System as a Black Woman," 13 Oct. 2018 Motherboard interviewed several security and international supply chain experts to get a better perspective on the story, and there's a lot of uncertainty. Sam Blum, Popular Mechanics, "New Report Claims More Evidence of Chinese Microchip Tampering," 9 Oct. 2018 That kind of uncertainty led to a recent National Academy of Sciences report that recommends three important qualities that estimates of SCC should prioritize. Cathleen O'grady, Ars Technica, "The US would suffer some of the biggest costs of climate change," 30 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'uncertainty.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of uncertainty

14th century, in the meaning defined at sense 1

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Last Updated

9 Dec 2018

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The first known use of uncertainty was in the 14th century

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English Language Learners Definition of uncertainty

: the quality or state of being uncertain

: something that is doubtful or unknown : something that is uncertain


un·​cer·​tain·​ty | \ˌən-ˈsər-tᵊn-tē \
plural uncertainties

Kids Definition of uncertainty

1 : lack of certainty : doubt Uncertainty made the days of waiting longer …— William H. Armstrong, Sounder

2 : something that is doubtful or unknown Life is full of uncertainties.

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