The Collaborative International Dictionary of English v.0.48:
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. [1913 Webster]WordNet (r) 3.0 (2006):
matchlock n 1: an early style of musket; a slow-burning wick would be lowered into a hole in the breech to ignite the charge