The term 'water-skiing' is a transparent 20th-century compound that logically adapts a winter sport to a summer environment. Its first element, 'water', originates from the Proto-Germanic watōr, designating the essential liquid medium on which the activity takes place. The second element, 'ski', was borrowed from Norwegian, tracing back to the Old Norse 'skíð' for a billet of wood or snowshoe, here repurposed as the gliding apparatus. The suffix '-ing', of Germanic origin, converts the implied verb 'to water-ski' into a noun denoting the sport itself, creating a modern, descriptive compound through the straightforward combination of its constituent morphemes.

Structure: water (liquid) + ski (gliding device) + ing (noun suffix) water: From Old English 'wæter', of Proto-Germanic origin, related to Dutch 'water' and German 'Wasser'. Functions as a noun root specifying the medium. ski: Borrowed from Norwegian, from Old Norse 'skíð' meaning "stick of wood, snowshoe". Functions as a noun root specifying the equipment. ing: From Old English '-ung', '-ing', a suffix forming nouns from verbs, denoting an action or its result. Functions as a derivational suffix forming the activity noun.