assertion

noun

as·​ser·​tion ə-ˈsər-shən 

a-

: 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.

Synonyms

• declaration
• claim
• insistence
• allegation

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

In one exchange, Nicholson challenged residents' assertion that the report said the welcome center would be located near a residential neighborhood, drawing a swift reaction from the crowd, according to a recording of the meeting. —Alexandria Burris, IndyStar, 2 July 2025

In line with the Constitution's assertion that the transfer of power happens at exactly noon on Jan. 20, Trump will take the presidential oath during the swearing-in ceremony. —Jordan Kellogg, The Enquirer, 2 July 2025

Even sophisticated test flows, complete with conditions and assertions, can be generated through natural language. —Asad Khan, Forbes.com, 2 July 2025

When investors have near-unanimous alignment with management—including the assertion that diversity programs drive growth, innovation, and long-term value—executives and the board have the strongest possible mandate to cement DEI as a corporate imperative. —Jim Edwards, Fortune, 1 July 2025

Word History

Etymology

see assert

First Known Use

15th century, in the meaning defined above

Phrases Containing assertion

• self-assertion

Rhymes for assertion

• cistercian
• coercion
• desertion
• exertion
• insertion
• mercian
• overexertion
• reassertion

Kids Definition

assertion

noun

as·​ser·​tion ə-ˈsər-shən 

a-

: the act of asserting

also : something asserted : declaration