The PM

Someone who uses your tears as lube

on various message boards you can PM or "Private Message" someone

When a woman is going through the pain of one of her internal organs shedding a layer. This may cause her to have a lower tolerance for incompetence and is why pmsing has such negative connotations.
If you happen to be the incompetent dingwad that pissed off a pmsing female, be kind to those around you and don't go off complaining about "how much of a bitch she is".
Caution: if a girl is angry don't just ask her if she is pmsing. Believe it or not that is one of the most infuriating things someone can say. Its like saying she cant be angry. Even if some shit just went down.

Pretty Much

A powerful spell that women are put under about once every month, which gives them the strength of an ox, the stability of a Window's OS, and the scream of a banshee. Basically, man's worst nightmare.

PMS (Pre-Menstrual Syndrome) or PMS-ing (Verb) has a wide array of symptoms but happens typically one to two weeks before someone’s period. As someone who gets periods and is probably PMS-ing right now, I want to tell people who don’t experience PMS that we cannot control how angry, sad, happy etc we get so please try to be understanding as we don’t mean to be mean and it’s hard for us. Of course you don’t have to go all out but just being willing to listen is enough.

what guys refer to as the worst time of the month.

but what i refer to it as, is the time of the month where men bitch and complain about not getting ass and blame everything on the woman.

yes, woman are more irritable at this time, but guys need to look at it through the woman's perspective.