Simple Definition of obsidian
: a dark natural glass that forms when lava cools
Full Definition of obsidian
: a dark natural glass formed by the cooling of molten lava
Origin of obsidian
New Latin obsidianus, from Latin obsidianus lapis, false manuscript reading for obsianus lapis, literally, stone of Obsius, from Obsius, its supposed discoverer
First Known Use: 1796
OBSIDIAN Defined for Kids
Definition of obsidian
: a smooth dark rock formed by the cooling of lava
Learn More about obsidian
Britannica.com: Encyclopedia article about "obsidian"
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