certainty

noun

cer·​tain·​ty ˈsər-tᵊn-tē How to pronounce certainty (audio)
plural certainties
Synonyms of certaintynext
1
: something that is certain
2
: the quality or state of being certain especially on the basis of evidence

Synonyms of certainty

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Using those powers could provide short-term budget certainty but would likely stoke further political volatility. — Jenni Reid, CNBC, 22 Oct. 2026 Global Fashion Agenda and ReHubs put the cost of building the recycling capacity Europe needs at 8-11 billion euros, and name demand certainty for sorters as one of the conditions for unlocking it. — Erik Lagerblad, Footwear News, 22 Oct. 2026 The deal gives the Timberwolves another year of cost certainty in managing future salary caps around the next maximum contracts anticipated for star guards Anthony Edwards and LaMelo Ball. — CBS News, 20 Oct. 2026 Why Family Business Makes This Harder Leading a company that your grandfather founded and your father helped build creates a particular kind of pressure to project certainty. — Flavio Maluf, Forbes.com, 20 Oct. 2026 See All Example Sentences for certainty

Word History

Etymology

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

Phrases Containing certainty

Rhymes for certainty

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Browse Nearby Words

certainness
certainty
certation
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Cite this Entry

“Certainty.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/certainty. Accessed 27 Oct. 2026.

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Kids Definition

certainty

noun
cer·​tain·​ty ˈsərt-ᵊn-tē How to pronounce certainty (audio)
plural certainties
1
: something certain
2
: the quality or state of being or feeling certain

More from Merriam-Webster on certainty

Britannica.com: Encyclopedia article about certainty

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