n. pl. di·ath·e·ses (-sēz′)
1. A hereditary predisposition of the body to a disease, a group of diseases, an allergy, or another disorder.
2. Grammar See voice.
[Greek, disposition, condition, from diatithenai, diathe-, to dispose : dia-, dia- + tithenai, to place, set; see dhē- in the Appendix of Indo-European roots.]
di′a·thetic (dī′ə-thĕtĭk) adj.
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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:
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.