Somebody call Webster’s, I have a new word for you: hanghair.
What is a hanghair? A hanghair is when the hair around your nipple is starting to grow back, and isn’t long enough to drape itself over the nipple, but is short enough to get caught in the fibers of your shirt. The result is a painful tug when your shirt moves, which then in turn pulls on the hanghair.
There you have it. Ouch.