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

Contraception, which includes birth control and Plan B, does not cause abortions, despite the assertion of some organizations. Julyssa Lopez, Glamour, "Brett Kavanaugh Referred to Birth Control as 'Abortion-Inducing Drugs' During Confirmation Hearings," 7 Sep. 2018 On March 24, while the President was traveling in Africa, he was asked about the assertion of Executive Privilege. Aaron Blake, Washington Post, "Brett Kavanaugh, Trump and what the Starr Report says about impeachment, annotated," 11 July 2018 Even for the Trump administration, this policy is a bold assertion of executive power to restrict immigration to the United States. Dara Lind, Vox, "The asylum ban — Trump’s boldest immigration power grab yet — explained," 12 Nov. 2018 The Saudi prosecutors cited Turkish evidence that the slaying was planned, contradicting a Saudi assertion just days ago that rogue officials from the kingdom killed him by mistake in a brawl inside their Istanbul consulate. Aya Batrawy, The Seattle Times, "Saudi Arabia again changes its story on Khashoggi killing," 25 Oct. 2018 President Trump was heavily criticized last week for making a baseless assertion that massive deaths on Puerto Rico did not happen. Andrew O'reilly, Fox News, "FEMA director says there's 'difference between direct deaths and indirect deaths' in Puerto Rico, following Trump remarks," 16 Sep. 2018 This month, prior to launching a missile attack on Syria's chemical weapons facilities, Trump took to Twitter, responding to the assertion that the Russians would block any missiles fired at Syria. Eric Adler, kansascity, "Obama photographer Pete Souza finds fame as 'the professional troll of Donald Trump' | The Kansas City Star," 18 Apr. 2018 In 1994, at the request of the NFL Players Association, the National Institute for Occupational Safety and Health (NIOSH) investigated the assertion that NFL players were at increased risk for premature death. Larry Holder,, "Friday's 'Dunc & Holder:' A Saints-Muhammad Wilkerson union?; Pelicans shoot for 11 in a row," 9 Mar. 2018 Nearly every assertion supporting that claim was untrue. Luke Darby, GQ, "Ex-Forbes Reporter: Trump Has Been Lying About the Size of His Fortune for Decades," 21 Apr. 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

2 Dec 2018

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 \

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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Comments on assertion

What made you want to look up assertion? Please tell us where you read or heard it (including the quote, if possible).


the figure or shape of a crescent moon

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