cer·tain·ty | \ ˈsər-tᵊn-tē \
plural certainties

Definition of certainty 

1 : something that is certain

2 : the quality or state of being certain especially on the basis of evidence

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Choose the Right Synonym for certainty

certainty, certitude, conviction mean a state of being free from doubt. certainty and certitude are very close; certainty may stress the existence of objective proof claims that cannot be confirmed with scientific certainty , while certitude may emphasize a faith in something not needing or not capable of proof. believes with certitude in an afterlife conviction applies especially to belief strongly held by an individual. holds firm convictions on every issue

Examples of certainty in a Sentence

Scientists still do not know with any degree of certainty why the disease spread so quickly. We cannot predict the outcome with absolute certainty. There was no certainty that the package would arrive in time. Her certainty about these complex moral issues is surprising.
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Recent Examples on the Web

The Navy is staying out of the program for now but future interest is a virtual certainty. Kyle Mizokami, Popular Mechanics, "Hellfire Tank Killer Replacement Enters Production," 27 June 2018 Your certainty, your control, and your bright, assertive confidence might suddenly be refracted, scattered, or interrupted. Claire Comstock-gay, The Cut, "How Much Will Mars Retrograde Ruin My Life?," 26 June 2018 But at this point, the only certainty with his group’s plans is uncertainty. Jordan Mcpherson, miamiherald, "David Beckham’s saw first-hand the mixed emotions about his proposed Miami MLS plan," 12 July 2018 The only certainty about the man is that he was expelled from Algeria with thousands of others before ending up in this transit camp in Arlit, a decaying mining town in the heat of the Sahara. Washington Post, "AP PHOTOS: Nameless migrant erases his history with silence," 25 June 2018 Reduce or expedite regulatory and permit processing requirements, to create more certainty and predictability in the development process. 2. Amy Chance, sacbee, ""Build a lot more of it": What California can do to solve its housing problem," 18 June 2018 Markets now seek consistency and certainty in Italian policies, but most of all, cooperation on the values that have turned the EU into the world’s second largest economic region. The Christian Science Monitor, "For Italy, all roads lead to EU values," 30 May 2018 His beliefs and certainty about the direction of his life cannot be moved -- the heckler's veto will not stop him from speaking the truth. Carl Lamarre, Billboard, "Kanye West to Hot 97's Morning Host Ebro Darden: 'I Love Donald Trump'," 23 Apr. 2018 Le Guin's work was full of that simultaneous ambivalence and certainty, drawn from her Taoist worldview of finding balance. Sean Gallagher, Ars Technica, "Author Ursula K. Le Guin has left us, and we’re now all Dispossessed," 24 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'certainty.' 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 certainty

14th century, in the meaning defined at sense 1

History and Etymology for certainty

Middle English certeinte, borrowed from Anglo-French certeinté, from certein, certain certain entry 1 + -té -ty

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Learn More about certainty

Phrases Related to certainty

almost a certainty

with certainty

Statistics for certainty

Last Updated

1 Sep 2018

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Time Traveler for certainty

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

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More Definitions for certainty



English Language Learners Definition of certainty

: the state of being or feeling certain about something

: something that is certain : a fact about which there is no doubt


cer·tain·ty | \ ˈsər-tᵊn-tē \
plural certainties

Kids Definition of certainty

1 : something that is sure Victory was a certainty.

2 : the quality or state of being sure She answered with certainty.

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Comments on certainty

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


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