whisky vs hard liquor

whisky and hard liquor both are nouns.

Word	Noun	Adjective	Verb	Adverb
whisky	Yes	No	No	No
hard liquor	Yes	No	No	No

As nouns, hard liquor is a hypernym of whisky; that is, hard liquor is a word with a broader meaning than whisky:

Other hypernyms of whisky include booze, hard drink, John Barleycorn, liquor, spirits, strong drink.

whisky (noun)	hard liquor (noun)
a liquor made from fermented mash of grain	an alcoholic beverage that is distilled rather than fermented