That's the American/Irish spelling. If it's a Scotch it's whisky.
This is not 100% true (George Dickel Tennessee Whisky comes to mind first) but it's close enough.
Comes from the word uisce, which is the Irish/Gaelic for water. Technically the Irish for whiskey itself though is 'uisce beatha', meaning 'water of life' ;)
For those unable to remember it without a mental aid:
WhiskEy:
IrEland
AmErica
Scotland has no E.. :)
> If it's a Scotch it's whisky.
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