DuckCorp Dico

Found 2 definitions

1.                 From The Jargon File (version 4.4.7, 29 Dec 2003):
                   
   
   
                   
                     
   OP
    //
       [Usenet; common] Abbreviation for “original poster”, the originator of a
       particular thread.
   
                   
                 

2.                 From The Jargon File (version 4.4.7, 29 Dec 2003):
                   
   
   
                   
                     
   op
    /op/, n.
       1. In England and Ireland, common verbal abbreviation for ‘operator’, as in
       system operator. Less common in the U.S., where sysop seems to be
       preferred.
       2. [IRC] Someone who is endowed with privileges on IRC, not limited to a
       particular channel. These are generally people who are in charge of the IRC
       server at their particular site. Sometimes used interchangeably with CHOP
    . Compare sysop.