n. pl. tri·chot·o·mies
1. Division into three parts or elements.
2. A system based on three parts or elements, especially the theological description of humans as consisting of body, soul, and spirit.
[New Latin trichotomia : Greek trikha, in three parts; see trei- in the Appendix of Indo-European roots + New Latin -tomia, -tomy.]
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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.