Assertion Meaning
/əˈsɜːʃən/Definition, CEFR level B2, pronunciation, examples, and quiz.
Listen pronunciation
Definition
nounThe act of asserting; positive declaration or averment.
nounSomething which is asserted; a declaration; a statement asserted.
Sentence Examples
It is important to note that his assertion is groundless.
Nobody will believe his assertion that he is innocent.
He was correct in his assertion that the minister had been lying.
Synonyms & Antonyms
Synonyms:
Antonyms:
None
CEFR Practice Quiz
His surprising ____ that the earth is flat shocked the scientists.
CEFR Practice Quiz (Alternate)
The scientist's bold ____ was supported by the new data from the lab.
Word Origin & History
From Middle English assercioun, from Latin assertiō. By surface analysis, assert + -ion.
Literary Quotations & Historical Citations
""Do tell us the real name of your country, and then when you are gone we shall know how to talk about you." To this luminous argument and remonstrance I could oppose nothing but assertion, and the whole party remained firmly convinced that I was for some reason or other deceiving them."
— 1869, Alfred Russel Wallace, The Malay Archipelago, volume II, London: Macmillan and Co., page 247:
"Suppose you are given the semifactual assertion, "even if Nora had liked mathematics then she would have became^([sic]) a scientist" and then you find out that Nora did in fact become a scientist."
— 2007 January 26, Ruth M. J. Byrne, The Rational Imagination: How People Create Alternatives to Reality, MIT Press, →ISBN, page 140:
"Drivers' union ASLEF bluntly rebuffed the claim of unofficial action, calling it a lie. And Avanti West Coast was unable to provide any proof for its assertion, when questioned by RAIL."
— 2022 August 24, Philip Haigh, “Network News: Union slams Avanti West Coast: 'lie' as services slashed”, in RAIL, number 964, page 6:
"However, that assertion is not backed up by US intelligence, sources told CNN. […] That claim came despite the Trump administration’s repeated assertions that the US had “obliterated” Iran’s nuclear program in military strikes last year."
— 2026 February 27, Jennifer Hansler, Natasha Bertrand, Kylie Atwood, Zachary Cohen, “Trump has claimed Iran is building missiles that could soon hit the US. Sources say that’s not backed up by US intelligence.”, in CNN, archived from the original on 03 Mar 2026:
"The user should be absolutely confident that the error issued is a real design error. In other words, a user should be confident that his assertion code is correct and that the assertion failure is not a false condition."
— 2006, Srikanth Vijayaraghavan, Meyyappan Ramanathan, A Practical Guide for SystemVerilog Assertions, page 284:
Explore More B2 Vocabulary Words
CEFR Practice Quiz
His surprising ____ that the earth is flat shocked the scientists.
CEFR Practice Quiz (Alternate)
The scientist's bold ____ was supported by the new data from the lab.