PJ

PJ is an abbreviation for:

Pararescue jumpers , see United States Air Force Pararescue
Partido Justicialista , an Argentine party
Person-year , the amount of work a person does on average in a year
Petajoule , 1 quadrillion joule, is a unit of measure for energy
Polícia Judiciária , Portuguese criminal police
Practical year in medical studies, see Medical studies #Practical year
Air Saint-Pierre , French airline (IATA code)
Johnston Atoll according to the ICAO code
Nationality mark for aircraft from the Netherlands Antilles, see aircraft registration number #List of nationality marks

a US Coast Guard flying boat type, see General Aviation PJ

PJ as a distinguishing mark on license plates: