flood meadow, floodplain (a flat grassy area adjacent to a river bed, subject to seasonal flooding) · mead, meadow · a comparatively large stream or small river
köken: From Middle High German ouwe (“terrain, landscape by water, in water; island”), from Old High German ouwa, from Proto-West Germanic *auwju (“floodplain, meadow; island”), from Proto-Germanic *awjō, from earlier *agwjō, ultimately from Proto-Indo-European *h₂ékʷeh₂ (“water”). Compare with Old Frisian ei, Swedish ö, Danish ø, Old Norse ey, Norwegian øy; also related to the modern German suffix -ach.
köken: Uncertain, possibly from Proto-Indo-European *der- (“to tear, split”) or *dʰel(h₂)- ("valley"), the existence of which is uncertain, see Proto-Germanic *dalą for more. Cognate with Avestan 𐬛𐬀𐬭𐬈𐬥𐬁 (darenā) and Sogdian 𐫔𐫡 (δar-).
köken: Derived from Proto-Turkic *buluŋ (“corner; direction; edge, side; isolated part of a landform”). Cognate with Old Turkic [script needed] (buluŋ, “edge; cardinal point”); Southern Altai булуҥ (buluŋ, “edge, corner; river creek”), Khakas пулунъ (pulunʺ, “corner; cape, promontory”), Yakut булуҥ (buluŋ, “isolated part of a forest, river, etc.”).
köken: Might be a learned borrowing from Chinese 草原 (cǎoyuán). Alternatively, it might be a reanalysis of 草(くさ)原(はら) (kusahara), applying the expected on'yomi to the spelling to imbue the term with a higher register. First cited with this sōgen reading to a newspaper article published in 1871.