Benrath line
noun
Ben·rath line
ˈben-ˌrät-
: one of a bundle of isoglosses crossing Germany roughly from Aachen and Düsseldorf to Frankfurt an der Oder and dividing High German to the south, with fricatives and affricates for proto-Germanic p, t, k, from the rest of the West Germanic speech area to the north and northwest, with proto-Germanic p, t, k remaining intact (as in E pipe, that, to, make, contrasted with G pfeife, das, zu, machen)
Word History
Etymology
translation of German benrather linie, from Benrath, Germany, near which the isogloss dividing High German machen "to make" from Low German maken crosses the Rhine