Pronunciation: (prō-tag'u-nist), [key]
1. the leading character, hero, or heroine of a drama or other literary work.
2. a proponent for or advocate of a political cause, social program, etc.
3. the leader or principal person in a movement, cause, etc.
4. the first actor in ancient Greek drama, who played not only the main role, but also other roles when the main character was offstage. Cf. deuteragonist, tritagonist.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.