Source : Webster's Revised Unabridged Dictionary (1913)

Flintlock \Flint"lock`\, n.
   1. A lock for a gun or pistol, having a flint fixed in the
      hammer, which on striking the steel ignites the priming.

   2. A hand firearm fitted with a flintlock; esp., the
      old-fashioned musket of European and other armies.

Source : WordNet®

flintlock
     n 1: a muzzle loader having a flintlock type of gunlock [syn: {firelock}]
     2: a gunlock that has flint embedded in the hammer; the flint
        makes a spark that ignites the charge