pyrotechnic (adj.)

1704, "of or pertaining to the use of fire" (a sense now obsolete); 1825, "of or pertaining to fireworks and the art of making them," from pyrotechny "the manufacture and use of gunpowder" (1570s), from pyro- "fire" + Latinized form of Greek tekhnē "art" (see techno-).

Figurative use, "brilliant, explosive display," is attested from 1847. Related: Pyrotechnical (1610s, from pyrotechny).