assertion
Americannoun
-
a positive statement or declaration, often without support or reason.
a mere assertion;
an unwarranted assertion.
- Synonyms:
- allegation, contention, claim
-
an act of asserting.
noun
-
a positive statement, usually made without an attempt at furnishing evidence
-
the act of asserting
Other Word Forms
- assertional adjective
- misassertion noun
- nonassertion noun
- overassertion noun
- reassertion noun
- superassertion noun
Etymology
Origin of assertion
1375–1425; late Middle English assercion < Latin assertiōn- (stem of assertiō ). See assert, -ion
Explanation
An assertion is a declaration that's made emphatically, especially as part of an argument or as if it's to be understood as a statement of fact. To assert is to state with force. So if someone makes an assertion, they’re not just trying out an idea — they really mean it. An assertion can also be an act that seems to make a statement without words. When your dog urinates in multiple places up and down your block, he's making an assertion of his dominance (also called "marking") over his "territory."
Vocabulary lists containing assertion
The New SAT: Words to Capture Tone
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The SAT: Words to Capture Tone, List 6
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"The Story of an Hour" by Kate Chopin
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Cranston confirmed that assertion in a separate interview.
From Los Angeles Times • Apr. 10, 2026
These trends emerged despite the mayor's assertion that London's per capita homicide rate has fallen to its lowest level on record.
From BBC • Apr. 9, 2026
Here is where I’m required to offer a throat-clearing assertion that everyone else’s marriage is a mystery, and that we can never know the depths of love or loathing from the outside.
From Salon • Apr. 8, 2026
This reinforces our assertion that investors, including market makers and oil traders, have no idea how to price oil to reflect war risks.
From Barron's • Apr. 8, 2026
That assertion attracted the full attention of law enforcement officials.
From "Just Mercy" by Bryan Stevenson
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.