Hero
Part of speech: noun
Definition: A real or mythical person of great bravery who carries out extraordinary deeds. A role model. The main protagonist in a work of fiction. A champion. An unwilling sufferer of an act of terrorism, terminal disease, or other tragedy. A large sandwich made from meats and cheeses; a hero sandwich Someone who possesses supernatural powers (in fiction) such as Spiderman.
Martyr
Part of speech: noun
Definition: One who willingly accepts being put to death for adhering openly to one's religious beliefs; notably, saints canonized after martyrdom.One who sacrifices his or her life, station, or what is of great value to him or her, for the sake of principle or to sustain a cause.(with a prepositional phrase of cause) One who suffers greatly and/or constantly, even involuntarily.
Part of speech: verb
Definition: To make someone into a martyr by putting him or her to death for adhering to, or acting in accordance with, some belief, especially religious; to sacrifice on account of faith or profession.To persecute.To torment; to torture.