Princeton's WordNet
assertion, averment, asseveration(noun)
a declaration that is made emphatically (as if no supporting evidence were necessary)
Synonyms:
assertion, averment, affirmation, statement, asseveration
Wiktionary
asseveration(noun)
An earnest affirmation or declaration of support.Synonyms:
avowal, averment
Dictionary of English Synonymes
asseveration(n.)
Synonyms:
declaration, assertion, avowal, protestation, affirmation, averment, assurance
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