köken: Via Middle Low German from Middle Dutch dûne, from Old Dutch dūna, from Proto-Germanic *dūnǭ. Middle Dutch origin is assured by the German -ü- (compare Süden). The more common Middle Low German form was dûne (with a back vowel -u-); this form may be originally Low German or an earlier borrowing from Dutch. Compare modern Dutch duin.
köken: From Middle Dutch dûne, from Old Dutch dūn, dūno, from Proto-West Germanic *dūnā, of uncertain origin, perhaps from Proto-Celtic *dūnom (“stronghold, rampart”).
köken: From Old Norse klettr (“crag”). Cognate with Norwegian klett (“cliff, summit”), Scots clett (“rock in the sea, separated from the cliffs on the mainland”), Old English clit, Ancient Greek κλιτύς f (klitús, “hill”). Doublet of klint.