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ex·oph·thal·mos also ex·oph·thal·mus

(ĕk′səf-thălməs)

Abnormal protrusion of the eyeball.

[From Greek exophthalmos, with prominent eyes : ex-, outside; see EXO- + ophthalmos, eye; see ok^w- in the Appendix of Indo-European roots.]

ex′oph·thalmic adj.

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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