A river of south-central Europe rising in southwest Germany and flowing about 2,850 km (1,770 mi) southeast through Austria, Slovakia, Hungary, and the Balkan Peninsula to the Black Sea. It has been a major trade route since the Middle Ages.
Word History: Across Europe, from Russia to England, there are rivers with names beginning with a d and also containing an n: the Don, the Dnieper, and the Dniester of Russia and Ukraine, the Danube of central Europe, and the six rivers called Don in Britain. All of these names come from the Proto-Indo-European word *dānu-, meaning "river" and derived from the root *dā- "to flow, flowing." In Avestan, the earliest Iranian language we know, dānu- means "river, stream." In modern Ossetic (the language of the Ossets, descendants of the Scythians, an Iranian tribe of the Russian steppes), don means "river, stream." This word appears in the name of the Don River of Russia. Dnieper and Dniester (earlier Danapris and Danastius, respectively) come from Scythian Dānu apara and Dānu nazdya ("the river in the rear" and "the river in front," respectively). The name of the six rivers called Don in Britain comes from the Celtic version of the "river" word, also *dānu-. This Celtic word survives more or less intact in the name of the Danube, which was called Dānuvius by the Romans. The presence of Celtic river names both in central Europe and in Britain attests to the Celts' earlier glory, and recalls a time when Celtic languages were spoken across Europe from the valley of the Danube in the east to Spain and Ireland in the west.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
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.