PN may refer to:
Pneumonia is an inflammatory condition of the lung affecting primarily the microscopic air sacs known as alveoli.
A pneumothorax is an abnormal collection of air in the pleural space that causes an uncoupling of the lung from the chest wall.
A pnictogen is one of the chemical elements in group 15 of the periodic table. This group is also known as the nitrogen family.
Rakim Allen (born December 9, 1991), better known by his stage name PnB Rock, is an American recording artist, record producer, and singer from Philadelphia, Pennsylvania.
Pneumatic tubes (or capsule pipelines; also known as Pneumatic Tube Transport or PTT) are systems that propel cylindrical containers through networks of tubes by compressed air or by partial vacuum.
A pneumatic motor (Air motor) or compressed air engine is a type of motor which does mechanical work by expanding compressed air.