as·​ser·​tion ə-ˈsər-shən How to pronounce assertion (audio)
: the act of asserting or something that is asserted: such as
: insistent and positive affirming, maintaining, or defending (as of a right or attribute)
an assertion of ownership/innocence
: 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 Despite the fact that 1.75 million people received hospice care in the United States last year, there is still a cruel misconception associated with it: entering hospice seems to be an assertion that the person is giving up on life, or is mere moments from death. Margaux Anbouba, Vogue, 22 Nov. 2023 Our Coverage of the Israel-Hamas War Al-Shifa Hospital: Israeli soldiers stormed Gaza’s largest hospital, searching for evidence to support Israel’s assertion that the complex doubles as a Hamas command center. Jennifer Schuessler, New York Times, 16 Nov. 2023 White House National Security Council spokesman John Kirby backed Israel’s assertions Tuesday. Kelly Kasulis Cho, Washington Post, 15 Nov. 2023 From there, the military continued to double down on the assertion that nothing had happened out of the ordinary at Roswell, culminating in an appearance by Ramey himself that night on the local NBC station in Fort Worth. WIRED, 14 Nov. 2023 But his career-long dedication to writing pithy biographical encyclopedia entries means the book seems to leap habitually from film to film without filling out its assertions. Mark Athitakis, Los Angeles Times, 10 Nov. 2023 The Cougars were picked to finish 13th in their first season in the 14-team Big 12, regarded as the nation’s best basketball conference, and Pope has been vocal in his assertion that the great equalizer can be the 3-ball. Mark Zeigler, San Diego Union-Tribune, 9 Nov. 2023 But reporting by Oregon Public Broadcasting and ProPublica casts doubt on the Corps’ assertions. Tony Schick, ProPublica, 31 Oct. 2023 This assertion of authority backfired, and large-scale rioting and attacks on white officers followed. Isaac Chotiner, The New Yorker, 30 Oct. 2023 See More

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

Word History


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

Dictionary Entries Near assertion

Cite this Entry

“Assertion.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2023.

Kids Definition


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

More from Merriam-Webster on assertion

Last Updated: - Updated example sentences
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