i·co·sa·he·dron (ī-kō′sə-hēdrən, ī-kŏs′ə-)
n. pl. i·co·sa·he·drons or i·co·sa·he·dra (-drə)
A polyhedron having 20 faces.
[Greek eikosaedron, from neuter of Greek eikosaedros, twenty-sided : eikosi, twenty; see wīktī- in the Appendix of Indo-European roots + -edros, -sided; see -HEDRON.]
i·co′sa·hedral (-drəl) adj.
(click for a larger image)icosahedron
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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:
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.