whisky sour vs whiskey sour

whisky sour and whiskey sour both are nouns.

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

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

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