Not

Not or NOT may refer to:

Language

 * Not, the general declarative form of "no", indicating a negation of a related statement that usually precedes
 * ... Not!, a grammatical construction used as a contradiction, popularized in the early 1990s

Science and technology

 * Negation, a unary operator in logic depicted as,  , or
 * Bitwise NOT, an operator used in computer programming
 * NOT gate, a digital logic gate (commonly called an inverter)
 * Nordic Optical Telescope, an astronomical telescope at Roque de los Muchachos Observatory, La Palma, Canary Islands

Other uses

 * Nottingham railway station (station code NOT)
 * Polish Federation of Engineering Associations (Naczelna Organizacja Techniczna)
 * Not, Missouri, an unincorporated community in the United States
 * "Not" (song), a 2019 song by Big Thief