P.A.
     n : an electronic amplification system used as a communication
         system in public areas [syn: {public address system}, {P.A.
         system}, {PA system}, {PA}]
     adv : by the year; every year (usually with reference to a sum of
           money paid or received); "he earned $100,000 per
           annum"; "we issue six volumes per annum" [syn: {per
           annum}, {per year}, {each year}, {annually}]
Source: WordNet® 2.0

pa
     n 1: an informal term for a father; probably derived from baby
          talk [syn: {dad}, {dada}, {daddy}, {papa}, {pappa}, {pater},
           {pop}]
     2: a short-lived radioactive metallic element formed from
        uranium and disintegrating into actinium and then into
        lead [syn: {protactinium}, {protoactinium}, {atomic number
        91}]
     3: a unit of pressure equal to one newton per square meter
        [syn: {pascal}]
     4: a Mid-Atlantic state; one of the original 13 colonies [syn:
        {Pennsylvania}, {Keystone State}]
     5: an electronic amplification system used as a communication
        system in public areas [syn: {public address system}, {P.A.
        system}, {PA system}, {P.A.}]
Source: WordNet® 2.0

PA
     Precision Architecture (HP)
     
     
Source: Virtual Entity of Relevant Acronyms