An Etymological Dictionary of the German Language/Kuppe
Kuppe, f., ‘peak, summit,’ adopted by the written language in the last century from MidHG.; in HG. the form would have pf. Koppe and Kuppe, as well as Kaupe (‘crest of birds,’ also termed Koppe, comp. OSax. coppod, ‘cristatus’ of snakes, under Kopf), are allied words, with the prim. meaning ‘point, extreme end,’ which belonged orig. to the strictly HG. permutated form Kopf. The further history of all these terms is obscure; under Kopf it is assumed that they are of genuine Teut. origin, though the possibility of their being blended with MidLat. and Rom. cupa, ‘beaker,’ is granted. In MidHG. kuppe, f. OHG. chuppa, f., means ‘covering for the head’ (espec. under the helmet); see Kopf.