Webster's 1828 dictionary's definition of "Martyr."
Noah Webster, An American Dictionary of the English Language, Volume 2 (New York: S. Converse, 1828), Entries for "Martyr" and "Martyrdom," [110]
M'ARTYR, n. [Gr. μάρτυρ, a witness.] One who, by his death, bears witness to the truth of the gospel. Stephen was the first christian martyr.
To be a martyr signifies only to witness the truth of Christ. South.
2. One who suffers death in defense of any cause. We say, a man dies a martyr to his political principles or to the cause of liberty.
M'ARTYR, v. t. To put to death for adhering to what one believes to be the truth; to sacrifice one on account of his faith or profession. Pearson.
2. To murder; to destroy. Chaucer.
M'ARTYRDOM, n. The death of a martyr; the suffering of death on account of one's adherence to the faith of the gospel.
He intends to crown their innocence with the glory of martyrdom. Bacon.