A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than wide and characteristically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partially secured heel. For climbing slopes, ski skins (originally made of seal fur, but now made of synthetic materials) can be attached at the base of the ski.
Originally intended as an aid to travel over snow, they are now mainly used recreationally in the sport of skiing.
Etymology and usage
The word ski comes from the Old Norse word "skíð" which means stick of wood or ski.
In Norwegian this word is usually pronounced [ˈʃiː]. In Swedish, another language evolved from Old Norse, the word is "skidor" (pl.).
English and French use the original spelling "ski", and modify the pronunciation. Prior to 1920, English usage of "skee" and "snow-shoe" is often seen. In Italian, it is pronounced as in Norwegian, and the spelling is modified: "sci". Portuguese, German and Spanish adapt the word to their linguistic rules: esqui, Schier (a German plural of Ski) and esquí. In Dutch, the word is "ski” and pronunciation was originally [ˈʃiː] as in Norwegian, but since approximately the 1960s changed to [ˈskiː]. Many languages make a verb form out of the noun, such as "to ski" in English, "skier" in French, "esquiar" in Spanish, "sciare" in Italian, "skiën" in Dutch, "esquiar" in Portuguese or "schilaufen" (as above also Ski laufen or Ski fahren) in German.