Try Our Apps


Gobble up these 8 terms for eating


[uh b-sid-ee-uh n] /əbˈsɪd i ən/
a volcanic glass similar in composition to granite, usually dark but transparent in thin pieces, and having a good conchoidal fracture.
Origin of obsidian
1350-1400; < 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 < Latin; see -an Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the Web for obsidian
Contemporary Examples
Historical Examples
British Dictionary definitions for obsidian


a dark volcanic glass formed by very rapid solidification of lava Also called Iceland agate
Word Origin
C17: from Latin obsidiānus, erroneous transcription of obsiānus (lapis) (stone of) Obsius, the name (in Pliny) of the discoverer of a stone resembling obsidian
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for obsidian

"dark, hard volcanic rock," 1650s, from Latin obsidianus, misprint of Obsianus (lapis) "(stone) of Obsius," name of a Roman alleged by Pliny to have found this rock in Ethiopia.

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
obsidian in Science
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.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Word Value for obsidian

Scrabble Words With Friends