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 Contrary to Trump's assertion, infections and deaths rose in some areas, with the total number of U.S. coronavirus deaths surpassing 80,000. Harold Maass, TheWeek, "10 things you need to know today: May 12, 2020," 12 May 2020 Critics of the assertion, or some would say mantra, that Bitcoin is a digital analogue to the precious metal could rightly point to a falling short-term correlation between the two assets throughout the fourth quarter of 2019. Brandon Kochkodin,, "Bitcoin Bolsters Claim as a Haven With Rally Topping Gold’s," 6 May 2020 Whitmer made the assertion on CNN, before the release of the latest number of deaths in Michigan related to the coronavirus. CBS News, "Michigan governor says "some of the worst racism" fueled protests over coronavirus response," 4 May 2020 Despite Karen Pence’s assertion that the vice president was unaware of the Mayo Clinic’s policy, there are nationwide mandates requiring people to wear face masks in public spaces. Erin Corbett,, "Karen Pence Is The Ultimate Karen For Explaining Why Mike Pence Won’t Wear A Mask," 30 Apr. 2020 Such assertions have frequently surfaced under the administration of U.S. President Donald J. Trump—and perhaps no more so than amid the global COVID-19 pandemic. Lourdes Medrano/undark, Popular Science, "Migrants don’t carry more viruses than anyone else," 27 Apr. 2020 Any assertion that Intuit does not support IRS Free File and free tax preparation is wholly false and ignores facts. Kristen Doerer, ProPublica, "What Is the New Deadline to File Taxes? A Coronavirus Update.," 13 Apr. 2020 Warren – who has pushed for universal child care as part of her 2020 presidential campaign – would agree with some of Trump's assertions. USA Today, "America's parents want paid family leave and affordable child care. Why can't they get it?," 3 Dec. 2019 Trump declined to provide details to back up his assertion, which contradicted a rare on-the-record statement from his own intelligence community which stated no such assessment has been made. Ivana Kottasová, CNN, "What you need to know about coronavirus on Friday, May 1," 1 May 2020

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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Time Traveler for assertion

Time Traveler

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

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Statistics for assertion

Last Updated

19 May 2020

Cite this Entry

“Assertion.” Dictionary, Merriam-Webster, Accessed 24 May. 2020.

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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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