26 synonyms for assertive such as authoritative, assaultive, and assured. Assertive is an adjective, and its antonyms are retiring, passive, and submissive.
Assaultive, assured, authoritative, believing in oneself, bold, bullish, commanding, confident, decisive, determined, dominant, domineering, feisty, firm, forceful, insistent, not backward in coming forward, positive, pushful, pushy, self-assertive, self-assured, self-confident, self-possessed, and strong-willed.