Source : Webster's Revised Unabridged Dictionary (1913)

Matchlock \Match"lock`\, n.
   An old form of gunlock containing a match for firing the
   priming; hence, a musket fired by means of a match.

Source : WordNet®

matchlock
     n : an early style of musket; had a slow burning wick that could
         be lowered into a hole in the breech to ignite the charge