Source : Free On-Line Dictionary of Computing

dirtball
     
        ({XEROX PARC}) A small, perhaps struggling outsider; not in
        the major or even the minor leagues.  For example, "Xerox is
        not a dirtball company".
     
        Outsiders often observe in the PARC culture an institutional
        arrogance which usage of this term exemplifies.  The
        brilliance and scope of PARC's contributions to computer
        science have been such that this superior attitude is not much
        resented.  - ESR
     
        [{Jargon File}]
     
        (1994-12-07)