firelock (n.)youdaoicibaDictYouDict
type of gun lock that uses sparks to ignite the priming, 1540s, from fire (n.) + lock (n.). Originally of the wheel-lock; transferred 17c. to the flintlock.
flint (n.)youdaoicibaDictYouDict
Old English flint "flint; a type of rock noted for hardness and for giving off sparks when struck," common Germanic (cognates Middle Dutch vlint, Old High German flins, Danish flint), from PIE *splind- "to split, cleave," from root *(s)plei- "to splice, split" (cognates: Greek plinthos "brick, tile," Old Irish slind "brick"), perhaps a variant of *spel- (1) "to split, break off." Transferred senses (hardness, etc.) were in Old English.
spark (v.)youdaoicibaDictYouDict
c. 1200, "to emit sparks," from spark (n.). Meaning "to affect by an electrical spark" is from 1889. Figurative meaning "stimulate, to trigger" first attested 1912. Meaning "to play the gallant, to court" is from the 17c. secondary sense of the noun. Related: Sparked; sparking.
sparkle (v.)youdaoicibaDictYouDict
c. 1200, "to shine as if giving off sparks," frequentative verb form of Middle English sparke (see spark (v.)). Meaning "emit sparks" is from late 15c. Related: Sparkled; sparkling.