Also called cinder. the more or less completely fused and vitrified matter separated during the reduction of a metal from its ore.

the scoria from a volcano.

waste left over after the re-sorting of coal.

to convert into slag.

Metallurgy . to remove slag from (a steel bath).

to form slag; become a slaglike mass.

noun

ashes , cinders , debris , dross , lava , recrement , refuse , residue , scoria