Word Study
rhyolite
CIDE DICTIONARY
rhyolite, n. [Gr. "rei^n to flow + -lite.].
A quartzose trachyte, an igneous rock often showing a fluidal structure. [1913 Webster]
OXFORD DICTIONARY
rhyolite, n. a fine-grained volcanic rock of granitic composition.
Etymology
G Rhyolit f. Gk rhuax lava-stream + lithos stone
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