Verses with the word martyr in the New Testament (2 verses):

Acts 22:20
And when the blood of thy martyr Stephen was shed, I also was standing by, and consenting unto his death, and kept the raiment of them that slew him.

Revelation 2:13
I know thy works, and where thou dwellest, even where Satan's seat is: and thou holdest fast my name, and hast not denied my faith, even in those days wherein Antipas was my faithful martyr, who was slain among you, where Satan dwelleth.