scoria

The story

1. Ancient Greek · derived fromσκωρία
2. Latin · derived fromscōria
3. English todayscoria

Inherited from Middle English, from Latin scōria, from Ancient Greek σκωρία (skōría), from σκῶρ (skôr, “dung”).

First known use, by meaning

• from 14th c. The slag or dross that remains after the smelting of metal from an ore.
• from 18th c. Rough masses of rock formed by solidified lava, and which can be found around a volcano's crater.