Where does “Δούναβης” come from?

Δούναβης (Greek) comes from Proto-Slavic Dunavь, from Gothic 𐌳𐍉𐌽𐌰𐍅𐌹, from Proto-Germanic Dōnawjaz, from Proto-Celtic Dānowyos, from Proto-Celtic Dānu, from Proto-Indo-European dʰenh₂- — to set in motion; to flow.

Ancestry of “Δούναβης”, step by step

StepLanguageWordMeaning
1Proto-SlavicDunavьDanube
2Gothic𐌳𐍉𐌽𐌰𐍅𐌹—
3Proto-GermanicDōnawjaz—
4Proto-CelticDānowyos—
5Proto-CelticDānu—
6Proto-Indo-Europeandʰenh₂-to set in motion; to flow
Every word from Proto-Indo-European dʰenh₂- →Every word from Proto-Celtic Dānu →Every word from Proto-Celtic Dānowyos →