noun ob·sid·i·an \əb-ˈsi-dē-ən\

: 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


noun ob·sid·i·an \əb-ˈsi-dē-ən\

Definition of OBSIDIAN for Kids

:  a smooth dark rock formed by the cooling of lava


Next Word in the Dictionary: obsidianitePrevious Word in the Dictionary: obsessusAll Words Near: obsidian
How to use a word that (literally) drives some people nuts.
Test your vocab with our fun, fast game
Ailurophobia, and 9 other unusual fears