assertion

noun

as·​ser·​tion ə-ˈsər-shən How to pronounce assertion (audio)
a-
: 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.

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.
Then-Media School Dean James Shanahan rebutted the assertion, saying the school had never sought to influence the paper's content. Cate Charron, IndyStar, 14 Oct. 2025 The site, with its grand plaza, was conceived as an assertion of civic pride under the lingering cloud of a presidential assassination perpetrated on the city's watch. Marc Ramirez, USA Today, 13 Oct. 2025 To help her students investigate this assertion, Rovito designed an in-class activity that invites them to become more than a student of history. JSTOR Daily, 11 Oct. 2025 What is the most confounding and terrible, however, is Gretchen’s assertion that Slade, the anti-Viagra, doesn’t get involved with the women on his own accord, but only engages because the women always talk about him. Brian Moylan, Vulture, 10 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Assertion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/assertion. Accessed 19 Oct. 2025.

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

Last Updated: - Updated example sentences
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