Power amplifier.
Public accountant.
Public Act.
Pennsylvania, a state of the United States of America
Papua, a province of Indonesia
Pará, a state of Brazil
Palestinian Authority
Proto-Algic (sometimes abbreviated PAc to distinguish it from Proto-Algonquian)
Proto-Athapaskan
Proto-Algonquian (sometimes abbreviated PAn to distinguish it from Proto-Algic, but usually just abbreviated PA with Proto-Algic being abbreviated PAc)
Any bird of the genus Leptoptilos, a branch of the stork family (Ciconiidae) native to India and Southeast Asia.
An assistant.
A lower-ranking officer who assists a higher-ranking officer with administrative affairs.
Assistant; who helps a higher-ranking officer.