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my·dri·a·sis

(mĭ-drīə-sĭs)

Dilation of the pupil of the eye, especially when excessive or prolonged, usually as a result of trauma, a medical disorder, or a drug.

[Latin mydriāsis, from Greek mudriāsis, perhaps from mudros, red-hot mass of metal in a forge (in reference to the more brilliant appearance of the dilated pupil to ancient physicians, as a result of light reflected off the fundus of the eye ); possibly akin to mudān, to be damp, dripping ( mudros perhaps originally referring to molten iron).]

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:

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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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