The definition of a cinder is a small piece of burned wood or coal that is still sparking even though it has been mostly burned.(noun)
A small leftover piece of firewood that is still solid and burning without flame is an example of a cinder.
See cinder in Webster's New World College Dictionary
Origin: ME & OE sinder, dross of iron, slag < IE base *sendhro-, coagulating fluid > Ger sinter, dross of iron, stalactite, sintern, to trickle, coagulate, Czech śadra, gypsum
See cinder in American Heritage Dictionary 4
Origin: Alteration (influenced by Old French cendre, ashes)
Origin: of Middle English sinder
Origin: , from Old English, slag, dross.
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