Old English wolcen 'cloud, sky', of West Germanic origin; related to Dutch wolk and German Wolke.

• loft from Old English:

  In Old English loft meant ‘air, sky’ as well as what was up in the air, an upper room. It comes from Old Norse, and shares a Germanic root with lift (Old English). Sky (Middle English) was also a borrowing from Scandinavian and originally meant ‘cloud’. The word was applied to a shade of blue in the mid 17th century; the phrase out of a clear blue sky, for something as unexpected as rain or thunder out of such a sky, made its appearance towards the end of the 19th century; the sky's the limit dates from the 1920s. When Anglo-Saxons wanted to talk about the sky they could also use the word wolcen, welkin in modern English, but now only used in the expression to make the welkin ring.