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obsidian

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noun ob·sid·i·an \əb-ˈsi-dē-ən\

Definition of obsidian

  1. :  a dark natural glass formed by the cooling of molten lava

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Origin and Etymology 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: 1794

OBSIDIAN Defined for English Language Learners

obsidian

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noun

Definition of obsidian for English Language Learners

  • : a dark natural glass that forms when lava cools

OBSIDIAN Defined for Kids

obsidian

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noun ob·sid·i·an \əb-ˈsi-dē-ən\

Definition of obsidian for Students

  1. :  a smooth dark rock formed by the cooling of lava

Learn More about obsidian

  1. See words that rhyme with obsidian Britannica.com: Encyclopedia article about obsidian

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