An Etymological Dictionary of the German Language/Kuß
Kuß, m., ‘kiss,’ from the equiv. MidHG. and OHG. kus (gen. kusses); corresponding to Du. kus, OSax. cus, cos (gen. -sses), AS. coss, OIc. koss, m.; a common Teut. word for ‘kiss,’ wanting only in Goth. (*kussus, comp. Goth. kukjan, East Fris. kükken, ‘to kiss’). A pre-Teut. root gut, gud, ‘to kiss,’ does not occur. Indubitable cognates are not found in the non-Teut. languages unless Ir. bus, ‘lip,’ and Gael. bus, ‘mouth with thick lips,’ are allied. —