Assertion adjectives are listed in this post. Each word below can often be found in front of the noun assertion in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing ASSERTION.
above, absolute, abstract, absurd, aggressive, arbitrary, arrogant, astonishing, astounding, audacious, authoritative, bald, bare, basic, blunt, bold, broad, calm, categorical, central, clear, common, complete, confident, conscious, constant, continued, contradictory
contrary, correct, curious, daring, definite, deliberate, direct, distinct, dogmatic, dogmatical, earlier, emphatic, erroneous, exaggerated, explicit, express, extraordinary, extravagant, extreme, factual, false, famous, fearless, final, firm, first, forceful, foregoing
formal, former, frequent, full, fundamental, further, general, gratuitous, grave, great, groundless, historical, idle, implicit, implied, important, impudent, incredible, individual, initial, known, last, later, latter, like, loose, loud, main
mere, modest, monstrous, naked, negative, new, next, old, only, open, opposite, original, other, own, paradoxical, particular, passionate, peremptory, persistent, personal, plain, political, positive, powerful, practical, present, previous, principal
proud, public, questionable, radical, rash, recent, reckless, remarkable, repeated, resolute, ridiculous, round, same, scientific, second, self, significant, silly, similar, simple, single, singular, solemn, startling, strange, strenuous, striking, strong
stronger, strongest, subsequent, successful, such, sweeping, theological, theoretical, third, triumphant, true, uncompromising, unequivocal, unfounded, universal, unproved, unqualified, unsupported, unwarranted, vague, vehement, very, vigorous, violent, wild
Hope this word list had the adjective used with assertion you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.