n. pl. di·chot·o·mies
1. A division into two contrasting parts or categories: the dichotomy between rural and urban communities; regards the division between nature and nurture as a false dichotomy.
2. Astronomy The phase of the moon, Mercury, or Venus when half of the disk is illuminated.
3. Botany Branching characterized by successive forking into two approximately equal divisions.
[Greek dikhotomiā, from dikhotomos, divided in two : dikho-, dicho- + temnein, to cut; see tem- in the Appendix of Indo-European roots.]
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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:
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