When someone places a 'tic-tac' (sweet) on the scrotum between the testies and grinds it about in the skin and covers it in ball sack sweat. This is then giver to a person who eats in unknowningly. You then inform the person that they have consumed a sack tac.
OMG that guy just ate my sack tac.

or

Jmal just chomped on my sack tac.
by captain cashew September 14, 2009
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