PN

PN may refer to:

Arts and entertainment

 * Purple Noon, a 1960 film
 * Patriotic Nigras, a griefing group in the game Second Life

Business and economics

 * Pacific National, a rail freight company in Australia
 * Participatory notes, issued to unregistered overseas investors in Indian stock markets
 * Pennsylvania Northeastern Railroad (reporting mark PN)
 * Promissory note, a contract where one party makes an unconditional promise in writing to pay a sum of money to another
 * West Air (China) (IATA airline code PN)

Navies

 * Pakistan Navy
 * Peruvian Navy
 * Philippine Navy
 * Portuguese Navy

Political parties

 * National Renaissance Front, Partidul Naţiunii, a political party in Romania
 * Partit Nazzjonalista, a political party in Malta
 * Perikatan Nasional, a political coalition in Malaysia
 * Partido Nacional (Uruguay), a political party in Uruguay

Places

 * Penang
 * Pitcairn Islands (ISO 3166-1 country code)
 * Palmerston North, a city in New Zealand
 * Province of Pordenone, a province in the autonomous region of Friuli-Venezia Giulia in Italy

Biology

 * Parenteral nutrition
 * Phylogenetic nomenclature, an approach to naming groups of living things

Electronics and computing

 * .pn, the country code top level domain (ccTLD) for Pitcairn Islands
 * p–n junction, a type of junction in electronics
 * Adobe Presenter, an Adobe software

Mathematics

 * Path graph of size $$n$$, denoted by $$P_n$$
 * Petri net, one of several mathematical modeling languages for the description of distributed systems
 * Polish notation, a prefix notation proposed by Jan Łukasiewicz
 * Polynomial vector spaces, denoted by $$\mathbb{P}_n$$
 * Pseudorandom number sequence

Other uses in science and technology

 * Part number, an identifier of a particular part design used in a particular industry
 * Particle number, in air-quality measurement
 * petanewton, a quadrillion newtons
 * Planetary nebula, in astronomy
 * Post-Newtonian expansion, an approximation of General Relativity
 * Proportional navigation, a concept in missile guidance systems
 * Pseudorandom noise, a deterministic sequence of pulses used in spread spectrum communication and rangefinding
 * Phosphorus mononitride (PN), an inorganic compound found in space

Other uses

 * Pottery Neolithic
 * Proper noun, a linguistic term for the name of an entity
 * Public News, an alternative newspaper in Houston (1982-1998)