Scotch Whisky, Irish Whiskey, Wisky and Wiski
Whisky may mean Scotch whisky to most of the world's population, but it is often wrongly substituted by the spelling whiskey, or even mis-spelt: wiskey, wisky. Much of this misunderstanding originates from the fact that there are a number of countries that distil their own whiskies (or whiskeys). Scotch whisky is by far and away the largest selling and most renowned; however, local spirits distilled in Ireland, Japan, Canada, America and India are also known as whiskey (whisky).
Scotch Whisky is always spelt without an 'e', be it Single Malt Whisky or Blended Scotch Whisky On occasions, particularly in the United States, Blended Scotch Whiskies will be shortened and asked for as Scotch.
Japanese Whisky, Canadian Whisky and Indian Whisky are also spelt without an 'e'. It is believed that Japanese Whisky is spelt this way as a result of Japan's first whisky distillers learning their trade in Scotland, in the early 1920's, thereafter adopting the Scottish convention. Canadian and Indian Whiskies, it is thought, in a similar vein embraced the spelling when they were part of the British Empire.
Historically, Irish Whiskey distillers inserted an 'e' to their spelling to differentiate their product from Scotch Whisky. American Whiskeys, both Bourbon and Rye, have in general taken-up the insertion of an 'e'. Though, as you would expect in this vast country with much Scottish ancestry, there are some distillers whom prefer to adopt the Scottish practice.
The word Whisky originates from the Scots Gaelic word Uisge Beatha: meaning the water of life, which was been Anglicised over time to Whiskybae. Finally being shorten to Whisky.
Uisge Beathe (or Usquebaugh in the Scots English spelling). itself is believed to be a Celtic translation of the ancient Latin acqua vitae (water of life).