<p><strong>Noun</strong></p><ul><li>The leading character, hero, or heroine of a drama or other literary work.</li><li>A proponent for or advocate of a political cause, social program, etc.</li><li>The leader or principal person in a movement, cause, etc.</li><li>The first actor in ancient Greek drama, who played not only the main role, but also other roles when the main character was offstage.</li><li>Physiology: agonist.</li></ul>