flintlock vs firelock

flintlock and firelock both are nouns.

Word	Noun	Adjective	Verb	Adverb
flintlock	Yes	No	No	No
firelock	Yes	No	No	No

As nouns, flintlock and firelock are synonyms defined as:

flintlock and firelock: a muzzle loader that had a flintlock type of gunlock

flintlock (noun)	firelock (noun)
an obsolete gunlock that has flint embedded in the hammer; the flint makes a spark that ignites the charge	a muzzle loader that had a flintlock type of gunlock
a muzzle loader that had a flintlock type of gunlock