syn·od·ic (sĭ-nŏdĭk) or syn·od·i·cal (-nŏdĭ-kəl)
1. Of or relating to a synod; synodal.
2. Relating to the period of time required for an object to complete a single orbital period, returning to the same position as observed from another object or position in space.
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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.