Verb- Act of showing support for the Seattle Seahawks by proudly sporting jersey's and other gear, and by displaying #12th man flags. 12ing should be done as often as possible if not all the time. If you see a fellow 12th man or woman 12ing, yell "SEA-HAWWWWKS!!!!" to show your pride. Post pictures of yourself 12ing whenever you can! GO HAWKS!
The frenzied fans of the Seahawks brought their 12th Man flag on vacation and posted a picture of themselves "12ing in Vegas" online

The Hawks fans were 12ing so hard at the game, the Whiners tries to impose noise control rules.
by Beastmode Allie January 13, 2014
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