Main entry: P.A., P.A. system, PA, PA system, public address system
Definition: an electronic amplification system used as a communication system in public areas
Main entry: PA, Pennsylvania, Keystone State
Definition: a Mid-Atlantic state; one of the original 13 colonies
Main entry: dad, dada, daddy, pop, pa, papa, pappa
Definition: an informal term for a father; probably derived from baby talk
Definition: a unit of pressure equal to one newton per square meter
Main entry: protactinium, protoactinium, atomic number 91, Pa
Definition: a short-lived radioactive metallic element formed from uranium and disintegrating into actinium and then into lead