A condition caused by excessive lint (commonly present in a new pair of underwear) clinging to the scrotum after the first use. The fuzz will fuse with ball sweat or Fermunda Cheese giving the appearance of an African-American's scrotum.
Trisha was disgusted at my Black Sack! She didn't believe that it was from my new pair of Fruit-of-the-Loom boxer briefs.
by RealTexarkanaTits July 12, 2013
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