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obsidian Line breaks: ob|sid¦ian
Pronunciation: /əbˈsɪdɪən/

Definition of obsidian in English:


[mass noun]
A hard, dark, glass-like volcanic rock formed by the rapid solidification of lava without crystallization.
Example sentences
  • Hard stones such as obsidian and rock crystal were added to the repertoire of the stone-vase maker.
  • The earliest mirrors were of obsidian, a black volcanic rock that could be carved and polished.
  • The presence of basalt and obsidian is a sign of volcanic activity and the instability of the earth's crust in this area.


Mid 17th century: from Latin obsidianus, error for obsianus, from Obsius, the name (in Pliny) of the discoverer of a similar stone.

Words that rhyme with obsidian

ascidian, Derridean, Dravidian, enchiridion, Euclidean, Floridian, Gideon, Lydian, meridian, Numidian, Pisidian, quotidian, viridian

Definition of obsidian in:

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