Nand

Nand[e1, e2, ...] is the logical NAND function. It evaluates its arguments in order, giving True immediately if any of them are False, and False if they are all True.

Examples

Nand[True, True]
(* False *)

Nand[True, False]
(* True *)

Nand[False, False]
(* True *)

Please visit the official Wolfram Language Reference for more details.