Some whiskeys

RYES

Hint: Grain used in a classic cocktail like a Manhattan. (This hint points to the key ingredient in rye whiskey, which is often associated with certain classic cocktails, nudging the solver toward the answer without directly stating it.)

The clue "Some whiskeys" leads to the answer "RYES" through a straightforward definition-based approach. "Whiskeys" refers to types of distilled alcoholic beverages, and "ryes" specifically denotes rye whiskey, a variety made primarily from rye grain.