As a Noun:
1. The main character in a book, play or film, who is admired or respected for his or her good qualities. English = hero.
2. A famous actor who often plays the role of the hero in films. English = movie star.
3. In books, comics, films, stories etc., to people who one is supposed to support because they are doing good things against people who are bad. Children's English = the goodies.