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