The Collaborative International Dictionary of English v.0.48:

Chalet \Cha*let"\, n. [F.]
   1. A herdsman's hut in the mountains of Switzerland.
      [1913 Webster]

            Chalets are summer huts for the Swiss herdsmen.
                                                  --Wordsworth.
      [1913 Webster]

   2. A summer cottage or country house in the Swiss mountains;
      any country house built in the style of the Swiss
      cottages.
      [1913 Webster]

WordNet (r) 3.0 (2006):

chalet
    n 1: a Swiss house with a sloping roof and wide eaves or a house
         built in this style