A military term used to described your ass. Comes from paratrooper training. When you land after a jump, you hit the ground and roll. This causes your 1st POC to be the balls of your feet. 2nd POC is your calves. 3rd POC is your back of your thigh. 4th POC is you ass, and 5th Point Of Contact is your shoulder blade.
The idiot who listed 5th point of contact with a similar definition needs to get his head out of his 4th point of contact.