obsidian

Estimated CEFR level: C2 — Proficiency

Estimated from word frequency; not an official CEFR classification.

Definition

noun acid or granitic glass formed by the rapid cooling of lava without crystallization; usually dark, but transparent in thin pieces

From Latin obsidianus; named after Obsidius, who was, according to Pliny, the Roman who discovered the stone in Aethiopia.

But it also became a field of wide-spread volcanic activity, and lavas and obsidians are constantly encountered among its gravels, sands, and shales. — The Book of the National Parks, Robert Sterling Yard
There is no doubt or question about that, although it is quite true that obsidian was found in other volcanic regions of different parts of the West. — The Young Alaskans on the Missouri, Emerson Hough
Turreted on all four corners, constructed of material which looked like blocks of natural glass, the fairylike structure was crowned by a gigantic tower of something which resembled obsidian. — Astounding Stories of Super-Science, December 1930, Various

Type a word, a sentence, a book title, or a link to an English article. WordNet and the Classics answer.

Try

A library of classics · a vault of words · instant etymology & meaning

From: —

Output

Worksheet Type (multi-select)

Scope

Difficulty

Max questions

0 words Min 50 words / Max 2,000 words