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i·o moth

(īō, ēō)

A large yellowish or reddish-brown North American moth (Automeris io) having a prominent eyelike spot on each hind wing.

[After IO, who was tormented by gadflies sent by Hera as a punishment (from the stinging spines of its larvae).]

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io moth

female (top) and male (bottom) io moths

Automeris io

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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