cinder
https://gyazo.com/e36c3c0246461ab9512e10290a0ad33d
source: By Doverbeach1 - Own work, Public Domain
noun
a small piece of partly burned coal or wood that has stopped giving off flames but still has combustible matter in it.
(石炭･木などの)燃えかす, 燃え残り
DERIVATIVES
cindery adjective
ORIGIN
Old English sinder ‘slag’, of Germanic origin; related to German Sinter. The similar but unconnected French cendre (from Latin cinis ‘ashes’) has influenced both the sense development and the spelling. Compare with sinter.