Meaning of ASSERTION in English
n. 25B6; noun
I questioned his assertion : DECLARATION, contention, statement, claim, opinion, proclamation, announcement, pronouncement, protestation, avowal; formal averment; rare asseveration.
an assertion of the right to march : DEFENCE, upholding; insistence on.
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012