Person who suffers persecution and death for advocating, refusing to renounce, and/or refusing to advocate a belief or cause, usually a religious one
A martyr ( mártys, 'witness' stem, martyr-) is someone who suffers persecution and death for advocating, renouncing, or refusing to renounce or advocate, a religious belief or other cause as demanded by an external party. In colloquial usage, the term can also refer to any person who suffers a significant consequence in protest or support of a cause. Wikipedia