- forceful - characterized by or full of force or strength (often but not necessarily physical); "a forceful speaker"; "a forceful personality"; "forceful measures"; "a forceful plan for peace"
Antonyms: forceless, unforceful, weak, wimpish, wimpy
- emphatic, forceful - forceful and definite in expression or action; "the document contained a particularly emphatic guarantee of religious liberty"
Antonym: unassertive (indirect, via assertive)