aquavit vs John Barleycorn

aquavit and John Barleycorn both are nouns.

Word	Noun	Adjective	Verb	Adverb
aquavit	Yes	No	No	No
John Barleycorn	Yes	No	No	No

As nouns, John Barleycorn is a hypernym of aquavit; that is, John Barleycorn is a word with a broader meaning than aquavit:

aquavit: Scandinavian liquor usually flavored with caraway seeds
John Barleycorn: an alcoholic beverage that is distilled rather than fermented

Other hypernyms of aquavit include booze, hard drink, hard liquor, liquor, spirits, strong drink.

aquavit (noun)	John Barleycorn (noun)
Scandinavian liquor usually flavored with caraway seeds	an alcoholic beverage that is distilled rather than fermented