obsidian

American  

[uhb-sid-ee-uhn] / əbˈsɪd i ən /

noun

1. a volcanic glass similar in composition to granite, usually dark but transparent in thin pieces, and having a good conchoidal fracture.

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obsidian British  

/ ɒbˈsɪdɪən /

noun

1. Also called: Iceland agate.  a dark volcanic glass formed by very rapid solidification of lava

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obsidian Scientific  

/ ŏb-sĭd′ē-ən /

1. A shiny, usually black, volcanic glass. Obsidian forms above ground from lava that is similar in composition to the magma from which granite forms underground, but cools so quickly that minerals do not have a chance to form within it.

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Etymology

Origin of obsidian

First recorded in 1350–1400; from Latin Obsidiānus, printer's error for Obsiānus “pertaining to Obsius,” the discoverer (according to Pliny) of a similar mineral in Ethiopia; replacing Middle English obsianus, from Latin

Example Sentences

She guides us into a quiet office with sleek wooden walls, gigantic computer monitors embedded within the walls, and a thick obsidian desk in the middle of the room.

From Literature

The shards, or clasts, have a glassy luster, making them look a lot like obsidian, a glass formed from lava when it cools very quickly.

From Salon

One gem is thought to be a rare, 2nd Century head of the Greek hero Hercules made from obsidian, a type of volcanic glass.

From BBC

And it comes in four newly named colors: obsidian, porcelain, bay and aloe.

From Seattle Times

The Cahuilla also charted trade corridors reaching from the Colorado River to the shores of the Pacific, where coastal tribes traded shell jewelry for obsidian tools and animal skins from the interior.

From Los Angeles Times

Related Words

• sunless
• unlighted
• unlit