Power-gaming: A player is making their character stronger in certain aspects. Such as stronger than an orc as a human, smarter than a wizard as an orc. They intentionally make their character as powerful as possible and ruin the fun of RP.
example: My nice human self is walking in the woods. I suddenly am set upon by a ferocious man-eating halfling. The halfing tackles me, so I attempt to throw him off of me. Suddenly the halfling tells me that I can't do that because he has latched onto me. So I attempt to slam him into a tree. But wait! He somehow doesn't suffer a pint of damage and still hangs onto me. He then proceeds to start "choking" me. So naturally I would pry at his arms, but he says he is super strong for a halfling and that wouldn't work.
This is an extremely unlikely scenario that shows a compulsive power-gaming behavior, also known as CPG. It is a common problem amongst newer RPers, or to those who don't intend to RP in the first place.
