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

Paramount took a swipe at that assertion on Monday — maintaining that Larry Ellison holds the majority of the trust’s assets and that Warner had not previously asked for a personal guarantee. —Boston Herald Staff, Boston Herald, 22 Dec. 2025

Turkish pro-government media celebrated it as an assertion of sovereignty, proof that Ankara would not be dictated to by Washington. —Bobby Ghosh, Time, 22 Dec. 2025

Jim Walden, a lawyer for Burzaco, denies Lopez’s assertion about Burzaco, who pleaded guilty to a corruption charge. —Hernan Lopez, Variety, 20 Dec. 2025

The December 3 Quinn Emanuel Letter largely relied for its assertions on partial summaries of inaccurate and incomplete newspaper reports that were not relevant to the evaluation of a potential transaction, while other assertions had no factual basis whatsoever. —Jill Goldsmith, Deadline, 17 Dec. 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