Source : Webster's Revised Unabridged Dictionary (1913)

Pa \Pa\ (p[aum]), n.
   A shortened form of {Papa}.

Source : WordNet®

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 : Free On-Line Dictionary of Computing

pa
     
         The {country code} for Panama.
     
        (1999-01-27)