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ich

(ĭk)

A contagious disease of freshwater fishes, caused by a ciliated protozoan (Ichthyophthirius multifiliis) and characterized by small white pustules on the skin and eyes.

[Short for New Latin Ichthyophthīrius, genus name : ICHTHYO- + Greek phtheir, louse.]

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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