assertion

noun

as·​ser·​tion ə-ˈsər-shən How to pronounce assertion (audio)
a-
Synonyms of assertion
: the act of asserting or something that is asserted: such as
a
: insistent and positive affirming, maintaining, or defending (as of a right or attribute)
an assertion of ownership/innocence
b
: a declaration that something is the case
He presented no evidence to support his assertions.

Synonyms of assertion

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Examples of assertion in a Sentence

the assertion that all men have certain unalienable rights is set forth in the Declaration of Independence made the unlikely assertion that gravity affects light
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.
Trump’s assertion Thursday that Palestinian Hamas militants and other armed groups had agreed to disarm had raised hopes of a turning point in the conflict. — Reuters, NBC news, 2 Aug. 2026 Greg Powers Photography Claiming to have the largest whiskey selection in America was always a dubious assertion. — Don Tse, Forbes.com, 1 Aug. 2026 Her decision to keep the child is neither an act of forgiveness nor a celebration of maternal instinct but an assertion of agency after nearly every other choice has been taken from her. — Encyclopedia Britannica, 29 July 2026 In defending the Islamic Republic, Blumenthal made one false or misleading assertion after another. — James Kirchick, The Atlantic, 29 July 2026 See All Example Sentences for assertion

Word History

Etymology

see assert

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of assertion was in the 15th century

Phrases Containing assertion

Rhymes for assertion

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Browse Nearby Words

assertible
assertion
assertional
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Cite this Entry

“Assertion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/assertion. Accessed 5 Aug. 2026.

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Kids Definition

assertion

noun
as·​ser·​tion ə-ˈsər-shən How to pronounce assertion (audio)
a-
: the act of asserting
also : something asserted : declaration

More from Merriam-Webster on assertion

Nglish: Translation of assertion for Spanish Speakers

Britannica.com: Encyclopedia article about assertion

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