A penis, specifically a bulbous or "chode" like member. Less of a "shlong" more of a "wang".
by Colly February 22, 2005
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The fat one is the proverbial "big, fat cock," usually used to describe something bad, often added on to "sucks" or "blows".
1:That song blows the fat one
2:this party sucks the fat one
3:it licked the fat one
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