on your period; menstruating.

derives from the fact that when you are menstruating, the blood is a conduit for the expelled egg, which will no longer be able to become a child. When it hits the toilet, you flush it down.
Geez, MaryJane, why can't we can't have sex just 'cause you're flushin' one down? I was really hoping to get my red wings tonight.
by Shmouse May 23, 2005
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