Definitions by RJ:)

PMS 

The seemingly supernatural phenomenon which occurs monthly (like the full moon), in which women are possessed by an angry spirit that seeks to make men's lives a mystery. This can refer to premenstrual stress, post menstrual stress, or just present menstrual stress.

"Better watch out, she's PMSing!"
"Wasn't her period last week though?"
"It's post menstrual stress."

PMS by RJ:) March 20, 2010