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A logic operator having the property that if P, Q, R, … are statements, then the NOR of P, Q, R, … is true if all statements are false, false if at least one statement is true. Derived from NOT-OR. Also known as Peirce stroke relationship.


Not OR.

The Boolean function which is true if none of its inputs are true and false otherwise, the logical complement of inclusive OR. The binary (two-input) NOR function can be defined (written as an infix operator):


Its truth table is:

A | B | A NOR B --+---+--------- F | F | T F | T | F T | F | F T | T | F

NOR, like NAND, 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 OR) A Boolean logical operation that is true if all inputs are false, and false if any input is true. An exclusive NOR (XNOR) is true if both inputs are the same. See flash memory and NAND flash.

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I say four, if not five," answered Don Quixote, "for never in my life have I had tooth or grinder drawn, nor has any fallen out or been destroyed by any decay or rheum.
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Fluttered with vague surmise; nor present nor future is clear.