cer·​tain·​ty ˈsər-tᵊn-tē How to pronounce certainty (audio)
plural certainties
: something that is certain
: the quality or state of being certain especially on the basis of evidence
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.
Recent Examples on the Web Making that work with a new contract is not a certainty, but the groundwork for it will start this week. Corey Masisak, The Denver Post, 5 June 2024 In making this decision there are no certainties, only tough calls. Geoff Colvin, Fortune, 30 May 2024 After years of pitching certainty, few knew what to expect from UCLA’s new, unproven arms. Houston Mitchell, Los Angeles Times, 27 May 2024 The contractor, Rhombus Power, would later use generative AI to predict Russia’s full-scale invasion of Ukraine with 80% certainty four months in advance, for a different U.S. government client. Frank Bajak, Fortune, 23 May 2024 See all Example Sentences for certainty 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'certainty.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

First Known Use

14th century, in the meaning defined at sense 1

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

Dictionary Entries Near certainty

Cite this Entry

“Certainty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/certainty. Accessed 19 Jun. 2024.

Kids Definition


cer·​tain·​ty ˈsərt-ᵊn-tē How to pronounce certainty (audio)
plural certainties
: something certain
: the quality or state of being or feeling certain

More from Merriam-Webster on certainty

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