scoria Meaning, Definition & Usage

  1. noun the scum formed by oxidation at the surface of molten metals
    slag; dross.

WordNet

Sco"ri*a noun
Etymology
L., fr. Gr. , fr. dung, ordure.
Wordforms
plural Scorlæ
Definitions
  1. The recrement of metals in fusion, or the slag rejected after the eduction of metallic ores; dross.
  2. Cellular slaggy lava; volcanic cinders.

Webster 1913