Yellow sock: When a man has to much anal sex, his anus becomes streched out and he no longer able to control his bowel movemnets. He is therefor forced to place a sock in his anus to stop stool for falling out. The sock inevitably turns the yellows-bown color and hense the name "yellow sock." Note this condition is common in the male prison population.
by zelgadiss May 08, 2007