A river of southwest Asia flowing about 2,800 km (1,740 mi) from central Turkey through Syria and into Iraq, where it joins the Tigris River to form the Shatt al Arab. Its waters were a major source of irrigation for the flourishing civilizations of ancient Mesopotamia.
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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.