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rhy·o·lite

(rīə-līt′)

A fine-grained extrusive volcanic rock, similar to granite in composition and usually exhibiting flow lines.

[Greek rhuāx, stream (from rhein, to flow; see sreu- in the Appendix of Indo-European roots) + -LITE.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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