From The Free On-line Dictionary of Computing (19 January 2023):
NAND
<logic> Not AND. The Boolean function which is true unless
both its arguments are true, the logical complement of
AND:
A NAND B = NOT (A AND B) = (NOT A) OR (NOT B)
Its truth table is:
A | B | A NAND B
--+---+---------
F | F | T
F | T | T
T | F | T
T | T | F
NAND, like NOR, forms a complete set of Boolean functions
on its own since it can be used to make NOT, AND, OR and any
other Boolean function:
NOT A = A NAND A
A AND B = NOT (A NAND B)
A OR B = (NOT A) NAND (NOT B)
(1995-01-24)