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 of assertion

• 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

Johnson’s sunny assertions that Republicans would defy history in the midterms, as voters traditionally have punished the president’s party in power, failed to hold. — Lisa Mascaro, Los Angeles Times, 4 Nov. 2026

As a most un-saintlike Mother Teresa, Dueñas gives voice to a seething, inconsolable fury, an assertion of pure, ferocious will, that exposes the preciousness of Ambrossi and Calvo’s poetic and structural conceits. — Justin Chang, New Yorker, 3 Nov. 2026

General assertions of lost profits, out-of-pocket expenses and reputational harm did not satisfy the requirement to plead special damages, Gayles wrote. — Antonio María Delgado, Miami Herald, 2 Nov. 2026

Here, the architecture distributes the congregation into a half circle, gathering them around the matter of their faith as a question rather than as an assertion. — Kristian Vistrup Madsen, Artforum, 1 Nov. 2026

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
• tertian
• overexertion
• reassertion

Kids Definition

assertion

noun

as·​ser·​tion ə-ˈsər-shən 

a-

: the act of asserting

also : something asserted : declaration