KeyDrop¶ $ wo 'KeyDrop[<|a -> 1, b -> 2, c -> 3|>, {a}]' <|b -> 2, c -> 3|> The operator form KeyDrop[keys] applies to an association later. $ wo 'KeyDrop[{b}][<|a -> 1, b -> 2, c -> 3|>]' <|a -> 1, c -> 3|>