An Etymological Dictionary of the German Language/Annotated/Binse
Binse (Swiss Binz), feminine, ‘rush,’ from the plural of the equivalent Middle High German binȥ, bineȥ, masculine, Old High German binuȥ, masculine; compare Old Saxon binut, Anglo-Saxon beonet, English bent, bentgrass, as well names of places, Bentley, Bentheim, with a Low German vowel. The most probable derivation is that given in the Old High German period, by Notker, from bi- and naȥ (see naß); hence literally ‘that which grows in wet places.’ LFranc. and Low German have a stem biusa corresponding to Dutch bies, Middle Low German bese, which are not cognate with Binse.