Patient transport ambulance

Post-Traumatic Amnesia

Parent-Teacher Association, a voluntary organization bringing together parents and teachers

Percutaneous transluminal angioplasty

Passenger Transport Authority

Plasma thromboplastin antecedent, another name for Factor XI

Paul Thomas Anderson, an American filmmaker

Peace Tree Ambassador, a name for young people (mostly children) who are inspired by the idea of Peace Tree Day, who are trying to spread peace around the world.

Promise to appear, also notice to appear, is a type of summons

Point of total assumption

Preferential Trade Arrangement

Pakistan Telecommunication Authority, a government agency responsible to regulate telecommunication services in Pakistan.

Pure Terephthalic acid, a starting compound for the manufacture of polyester.

Primetime Adventures, an indie role-playing game

Public Transport Authority of Western Australia

Pits, Tits, Ass: The three basics parts of the body to wash when a proper shower isn't available.