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.

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.
Vote banks had thus turned into vehicles of collective political assertion. — Asim Ali, Time, 24 Oct. 2026 Trump has repeatedly denied ordering the disruption of Starlink, despite Musk's public assertions that the order would have come from the White House. — Garrett Downs, CNBC, 23 Oct. 2026 Price’s assertion didn’t allay the concerns of experts that ProPublica spoke with. — Nat Lash, ProPublica, 23 Oct. 2026 The lawyer pushed back on the prosecution’s assertion that Romero didn’t turn himself in. — Molly Crane-Newman, New York Daily News, 22 Oct. 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

Browse Nearby Words

Cite this Entry

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

Kids Definition

assertion

noun
: the act of asserting
also : something asserted : declaration

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