PSA

from WordNet (r) 3.0 (2006)

PSA
    n 1: a protein manufactured exclusively by the prostate gland;
         PSA is produced for the ejaculate where it liquifies the
         semen and allows sperm cells to swim freely; elevated
         levels of PSA in blood serum are associated with benign
         prostatic hyperplasia and prostate cancer [syn: {prostate
         specific antigen}, {PSA}]

from The Free On-line Dictionary of Computing (8 July 2008)

PSA

   Problem Statement Analizer.  See {PSL/PSA}.

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

PSA
       Python Software Activity (Python)