2P

2P may refer to:

Science

 * 2P/Encke, official designation of Comet Encke
 * 2p, an arm of Chromosome 2 (human)
 * 2p, an atomic orbital for electrons
 * Two-photon absorption
 * Two-photon excitation microscopy

Transportation

 * Airphil Express, a Philippines airline, IATA code 2P
 * LMS Class 2P 4-4-0, a British locomotive

Other

 * 2P, a 408mm artillery piece from the Soviet Union
 * 2p, a two pence British coin
 * 2P, rapper 2 Pistols
 * 2P reserves, proven reserves of fossil fuels
 * 2P, meaning "player 2" in fandoms which can include inverting a character's personality and appearance