noun

assertion

uh-SUR-shuhn

noun

A firm, confident statement, especially one made without offering proof.

"His assertion that the deal was legal was later disproved."

"The report is full of assertions but light on evidence."

In computing, a statement in code that checks whether a condition is true at that point, used to catch bugs.

"The programmer added an assertion to catch invalid input early."

How to Use Assertion

Learner’s notes

In plain EnglishA confident claim or statement, which may or may not be backed up by evidence.

Common pairings

bold assertion unsupported assertion make an assertion

assertions plural

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His _____ that the deal was legal was later disproved.

From Latin assertio, from assert- (see "assert"), plus the noun suffix "-ion".

accusation allegation censure charge crimination impeachment

accusation retreat deem attack penalty charge censure condemnation

ion lion Zion Dion Sion union scion Orion Onion action minion bunion

accusation allegation censure charge crimination impeachment retreat deem attack penalty condemnation