An Etymological Dictionary of the German Language/Mehltau

by Friedrich Kluge

Mehltau, m., ‘mildew, blight,’ corrupted from the equiv. MidHG. miltou, n., OHG. mili-tou, n.; comp. AS. meledeáw (miledeáw), E. mildew. The opinions as to the origin of the first component are various. The most probable derivation is that from Goth. miliþ, n., ‘honey’ (comp. OIc. milska, f., ‘sweet drink’), to which in West Teut. a subst. mili (Gr. μέλι, stem μέλιτ-, Lat. mel) is possibly akin; hence Mehltau, ‘honeydew’?. It is less probable that the word was borrowed from or was primit. allied to the equiv. Gr. μίλτος, so that Tau may have been an explanatory addition (comp. Lindwurm and Windhund). It is also possible that OHG. mili-, AS. mele-, mile-, is connected with Mehl, and a special formation from the root mel, ‘to grind.’ In that case the ModHG. change of Miltau into Mehltau is warranted by etymology; Mehltau is defined as ‘a greyish-white, meal-like coating on plants in summer.’