a·dieu (ə-dy, ə-d)
Used to express farewell.
n. pl. a·dieus or a·dieux (ə-dyz, ə-dz)
[Middle English, from Old French a dieu, (I commend you) to God : a, to (from Latin ad; see AD-) + Dieu, God (from Latin deus; see dyeu- 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.