whiskey sour vs whisky sour

whiskey sour and whisky sour both are nouns.

Word	Noun	Adjective	Verb	Adverb
whiskey sour	Yes	No	No	No
whisky sour	Yes	No	No	No

As nouns, whiskey sour and whisky sour are synonyms defined as:

whiskey sour (noun)	whisky sour (noun)
a sour made with whiskey	a sour made with whiskey