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

Speaking to Fox News Digital, Kravetz dismissed assertions that her group relies on DSA tactics, emphasizing that CVPE supporters span the political spectrum. — Louis Casiano, FOXNews.com, 9 Oct. 2026

Multiple individuals within the world of independent film backed up Skolnick’s assertions about his reputation and the wider industry to IndieWire. — Adam B. Vary, IndieWire, 9 Oct. 2026

The way a book has been handled, underlined, and annotated, as well as the creases in the corners of pages, are reminders of this dispute and of the reader’s assertion of ownership that will remain forever on their bookshelves. — Literary Hub, 8 Oct. 2026

At the meeting, Maitland Mayor John Lowndes, a Democrat who is running against Brodeur for the state Senate seat, spoke out against Dorworth’s assertion that the county’s development process was rigged in favor of preserving the rural boundary. — Martin E. Comas, The Orlando Sentinel, 8 Oct. 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