The Collaborative International Dictionary of English v.0.48:
Pistoleer \Pis`to*leer"\, n. [Cf. F. pistolier.] One who uses a pistol. [R.] --Carlyle. [1913 Webster]WordNet (r) 3.0 (2006):
pistoleer n 1: someone armed with a pistol (especially a soldier so armed)