as·​ser·​tion | \ ə-ˈsər-shən How to pronounce assertion (audio) , 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

The city, which declined to comment on the lawsuit, disagrees with the company’s assertion that its fuel cells are inherently cleaner. Thy Vo, The Mercury News, "Bloom Energy sues Santa Clara for undermining its technology," 13 June 2019 Ross has denied assertions that the citizenship question was inspired by efforts to suppress census participation by immigrants, including those in the country legally, who may tend to vote for Democrats. Chris Strohm, Fortune, "House Panel Votes to Hold Barr, Ross in Contempt of Congress: What Happens Now," 13 June 2019 Rhea instead provided a short statement denying new Sheriff Jonathon Horton's assertion that Entrekin refused to speak with him after the election. Connor Sheets |,, "After losing reelection, these Alabama sheriffs took it out on their successors - and the public," 12 June 2019 Some of Ptolemy’s assertions were already being questioned by Novara. National Geographic, "Copernicus's revolutionary ideas reorganized the heavens," 9 Apr. 2019 The Twitter feed of NRA-TV, an arm of the National Rifle Association, hailed Gaskill as proof that the group's assertion that armed guards--or teachers--is a better response to school shootings than gun control of any kind. The Washington Post,, "School resource officer helped stop gunman at Maryland high school," 20 Mar. 2018 Trump recently said drug smugglers don’t use ports of entry, an assertion flatly contradicted by his drug enforcement personnel. Hope Yen, The Seattle Times, "AP fact check: Trump isn’t holed up nonstop at White House," 14 Jan. 2019 President Trump, too, has long claimed widespread voter fraud took place in the 2016 election, an assertion that has not been substantiated. Kaitlyn Schallhorn, Fox News, "North Carolina hit with subpoena for millions of voter records by federal officials investigating fraud," 6 Sep. 2018 That earlier assertion, in turn, backtracked from an initial statement that Saudi authorities knew nothing about what happened to the columnist for The Washington Post, who vanished after entering the consulate Oct. 2. Aya Batrawy, The Seattle Times, "Saudi Arabia again changes its story on Khashoggi killing," 25 Oct. 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

17 Jun 2019

Look-up Popularity

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 How to pronounce assertion (audio) \

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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