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mass sociogenic illness

An illness occurring in a group of people with a shared social setting, such as a school, workplace, or military group, and characterized by a usually rapid onset and symptoms such as nausea, dizziness, fainting, headache, or skin rash.

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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