Definition of: cinder

(sin′dər) noun
1. Any partly burned combustible substance, before it has been reduced to ashes, especially when combustion has entirely ceased.
2. A thoroughly charred bit of wood, coal, or the like; an ember.
3. plural Ashes.
4. A scale of iron oxide thrown off in forging; also, light slag.
5. plural Geol. Fragments of scoriaceous lava explosively ejected from a volcano during an eruption; scoria.
—v.t. To burn or reduce to a cinder. [OE sinder; infl. in form by L cinis, cineris ash]
—cin′der·ry adjective