Mid 16th century. From Middle French pistolet small firearm, pistol, apparently from pistole (although this is first attested slightly later) + -et; compare also slightly earlier pistolet.
pistolet2
/ˈpɪstəlɛt//ˈpɪstəlɪt/
Now historical
noun
A Spanish gold escudo; (also) a Spanish double-escudo; = pistole. Also occasionally: any of various other gold coins of the 16th and 17th centuries.
Origin
Mid 16th century. From French †pistolet, of uncertain origin; perhaps the same word as pistolet (although this is first attested slightly later), with reference to the small size of the coins.