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pit·y·ri·a·sis

(pĭt′ĭ-rīə-sĭs)

n. pl. pit·y·ri·a·ses (-sēz′)

Any of various skin diseases of humans and animals, characterized by epidermal shedding of flaky scales.

[Greek pitūriāsis, from pitūra, grain husks, bran, dandruff, perhaps from dissimilation of *putūra; see pau-² in the Appendix of Indo-European roots, or akin to pitulos, repetitive striking; see pet- in the Appendix of Indo-European roots.]

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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