as·ser·tion | \ə-ˈsər-shən, a-\

Definition 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.

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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

Sotomayor compared Trump's policy to the internment of Japanese Americans that was upheld by the Supreme Court during World War II, an assertion that drew a scold from Roberts, but which resonated with Carson and Ellison. Richard Wolf, Indianapolis Star, "Supreme Court ruling on Donald Trump's travel ban a 'shameful sanctioning of discrimination,' Andre Carson says," 26 June 2018 Friday's filings offered the fullest picture to date of the kinds of assertions and evidence to be presented in the case that began in 2014 and that ultimately could affect admissions policies and racial affirmative action nationwide. Joan Biskupic, CNN, "Lawsuit: Harvard ranks Asian-Americans lower on personality traits," 15 June 2018 Spiegel said in response to one of the memo’s assertions: that Snap hired women in revealing costumes designed to look like Snapchat’s deer filter to serve food and pose for pictures at a company party. Maya Kosoff, The Hive, "“People Are Going to Make Mistakes”: Evan Spiegel Defends Snap Against Charges of Sexism," 30 May 2018 Assistant District Attorney Deborah Watson-Stokes, the prosecutor who had rejected Nenner’s assertions about Morrison more than a year earlier, tried to rebut the evidence. Mensah M. Dean,, "3 charged, none convicted: Why a North Philly murder remains unsolved," 29 May 2018 That’s just one of the skeptical assertions echoed by Republicans on the U.S. House of Representatives Science, Space, and Technology Committee this week. Katie Langin, Science | AAAS, "Top stories: HPV vaccine debate, 2000-year-old pollution, and a lawmaker’s views on sea level rise," 18 May 2018 Trump’s justification for abandoning the deal rests on a series of flawed assertions and a disregard for the value of agreement, known as the Joint Comprehensive Plan of Action (JCPOA). Kelsey Davenport, Time, "Trump's Reckless Violation of the Iran Deal Jeopardizes U.S. National Security," 9 May 2018 The officer didn’t believe Reggie could actually be a student, regardless of the partygoers’ assertions, while the students were surprised that campus security even carried guns. Pilot Viruet, The Verge, "In season 2, Dear White People takes on trauma and the internet," 4 May 2018 As might be expected, Ford and Reiche vocally and thoroughly reject Stardock's assertion in their response. Lee Hutchinson, Ars Technica, "Star Control countersuit aims to invalidate Stardock’s trademarks [Updated]," 22 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'assertion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of assertion

15th century, in the meaning defined above

History and Etymology for assertion

see assert

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Statistics for assertion

Last Updated

7 Oct 2018

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Time Traveler for assertion

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

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More Definitions for assertion


as·ser·tion | \ə-ˈsər-shən \

Kids Definition of assertion

1 : the act of stating clearly and strongly or making others aware the assertion of his innocence

2 : something stated as if certain They did not believe me despite my assertions.

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