ad·verse (ăd-vûrs, ădvûrs′)
1. Acting or serving to oppose; antagonistic: adverse criticism.
2. Contrary to one's interests or welfare; harmful or unfavorable: adverse circumstances.
3. Moving in an opposite or opposing direction: adverse currents.
[Middle English, from Old French advers, from Latin adversus, past participle of advertere, to turn toward : ad-, ad- + vertere, to turn; see wer-2 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.