The Collaborative International Dictionary of English v.0.48:

Whisky \Whis"ky\, Whiskey \Whis"key\, n. [Ir. or Gael. uisge
   water (perhaps akin to E. wash, water) in uisgebeatha
   whiskey, properly, water of life. Cf. Usquebaugh.]
   An intoxicating liquor distilled from grain, potatoes, etc.,
   especially in Scotland, Ireland, and the United States. In
   the United States, whisky is generally distilled from maize,
   rye, or wheat, but in Scotland and Ireland it is often made
   from malted barley.
   [1913 Webster]

   Bourbon whisky, corn whisky made in Bourbon County,
      Kentucky.

   Crooked whisky. See under Crooked.

   Whisky Jack (Zool.), the Canada jay (Perisoreus
      Canadensis). It is noted for its fearless and familiar
      habits when it frequents the camps of lumbermen in the
      winter season. Its color is dull grayish blue, lighter
      beneath. Called also moose bird.
      [1913 Webster] Whiskyfied

The Collaborative International Dictionary of English v.0.48:

Whiskey \Whis"key\, n.
   Same as Whisky, a liquor.
   [1913 Webster] Whiskey

The Collaborative International Dictionary of English v.0.48:

Whiskey \Whis"key\, Whisky \Whis"ky\, n.; pl. Whiskeysor
   Whiskies. [See Whisk, v. t. & n.]
   A light carriage built for rapid motion; -- called also
   tim-whiskey.
   [1913 Webster] Whiskey Ring

WordNet (r) 3.0 (2006):

whiskey
    n 1: a liquor made from fermented mash of grain [syn: whiskey,
         whisky]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "whiskey":
   Angostura bitters, Canadian, Canadian whiskey, Cognac,
   Grand Champagne, Irish, Irish whiskey, Kirsch, Scotch,
   Scotch whiskey, absinthe, bitters, blended whiskey, bourbon,
   brandy, clean rum, eau de vie, gin, grog, light whiskey,
   malt whiskey, marc, mescal, moonshine, ouzo, plum brandy, raki,
   rum, rye, rye whiskey, schnapps, slivovitz, spirits, tequila,
   vodka