du·o·dec·i·mal (d′ə-dĕsə-məl, dy′-)
1. Of, relating to, or based on the number 12: the duodecimal number system.
2. Of or relating to twelfths.
[From Latin duodecimus, twelfth, from duodecim, twelve : duo, two; see dwo- in the Appendix of Indo-European roots + decem, ten; see dek 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:
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.