I've never seen that stat. I figured maybe I was just missing something or not thinking straight, so I checked several Baseball statistic references. I can't find that stat listed on any of them.
The stat is "APP" - pitching appearances.
There is no such stat. If you're seeing it on a stat sheet, it may refer to some kind of "total."
OPS Stat in MLB is a metric that adds on base percentage to slugging percentage.
Stat is he/she/it stands
The baseball stat WC means Wild Card as how many games back in the league race a team is.
stat is an abbreviation for statistique, (statistical / statistics)
Baseball America may have formed a stat for this category.
There is no stat concerning OWAR in baseball. You can check the Baseball Almanac for assurance.
Stat veritas means literally "The truth stands", or "Truth endures".
Typically, SO refers to "Strike Out". This stat applies to any type of pitcher (SP, RP).