Martyr, mârtyris, penu. corr. com. gen. Latinè testis dicitur. A witnesse: a martyre.
Lewis and Short: Latin dictionary
martyr, ris, comm., = ma/rtur, a witness; esp. one who by his death bears witness to the truth of the Christian religion, a martyr (eccl. Lat.): salvete flores Marty rum, Prud. Cath. 12, 125; Vulg. Apoc. 17, 6 —In fem.: Perpetua, fortissima martyr, Tert. Anim. 55.