Source : Webster's Revised Unabridged Dictionary (1913)

Protomartyr \Pro"to*mar`tyr\, n. [LL., fr. Gr. ?; ? first + ?
   martyr: cf. F. protomartyr. See {Proto-}, and {Martyr}.]
   The first martyr; the first who suffers, or is sacrificed, in
   any cause; -- applied esp. to Stephen, the first Christian
   martyr.