au·rochs (ourŏks′, ôrŏks′)
n. pl. aurochs
1. A wild ox (Bos primigenius) of Europe, northern Africa, and western Asia that became extinct in the 17th century and is believed to be the ancestor of domestic cattle. Also called urus.
2. See wisent.
[Obsolete German, variant of German Auerochs, from Middle High German ūrohse, from Old High German ūrohso : ūro, aurochs + ohso, ox; see uks-en- 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.