An Etymological Dictionary of the German Language/Annotated/Fluder
Fluder, neuter ‘mill trough,’ from Middle High German vlôder, neuter, ‘flowing, flooding, mill trough,’ Old High German flôdar, ‘flood of tears.’ In Gothic *flauþr, neuter, is probably to be assumed, based upon a root flau, flu; compare Old High German flouwen, flęwen, Middle High German vlouwen, vlöun, ‘to wash, rinse.’ The properly sense of the word is exactly that of fließen; compare Old Icelandic flau-mr, ‘current, flood’; for pre-Teutonic plu, see under fließen.