1 definition by fatlala

The sport of being the biggest fan (or twelfth man), particularly in football. Every article of clothing, including those one can't see, is ritualistic and perhaps unwashed for superstitious reasons. The surface of the skin is painted, tattooed, and bleeds team colors (especially Seahawk green). SYN: competitive out-fanning.
- Yo, check out his green-and-blue striped overalls.
- Yeah, he is twelftherer than anyone here.
by fatlala September 22, 2014
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