pa
名词 pa:
an informal term for a father; probably derived from baby talk
同义词:dad, dada, daddy, 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, atomic number 91
a unit of pressure equal to one newton per square meter
同义词:pascal
a Mid-Atlantic state; one of the original 13 colonies
同义词:Pennsylvania, Keystone State
an electronic amplification system used as a communication system in public areas