KeyDropFrom

KeyDropFrom[a,key] changes the association a by dropping the element with the specified key.

KeyDropFrom[a,{key1,key2,...}] drops the elements with keys keyi.

Examples

assoc = <|"a" -> 1, "b" -> 2, "c" -> 3|>;
KeyDropFrom[assoc, "b"];
assoc
(* <|"a" -> 1, "c" -> 3|> *)

Please visit the official Wolfram Language Reference for more details.