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1.
A slang word used for the area between the scrotum (or ball sack) and the rectum. This has also been called the "Gooch" and "Taint", but its scientific name is the perineum. The Sactum is a word that also defines the perineum.

Origin: Internet Film Reviwer "Luke Mochrie" accidentally called the movie Sanctum "Sactum", one of his fans "Christopher Harrison", proceeded refer to this as the area between the ball sack and the rectum.
After being insulted several times by his friend John. David told John he could lick his Sactum.
by BatmanofSparta February 04, 2011