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A disease that afflicts only Mets fans. It is the only means of survival for many fans as it wipes their memory clean from the disastrous past season.
In order to Avoid mental anguish, a loyal fan of the NY Mets must employ METSheimers.

John: Hey, remember when the Mets lost 10-2 last year?
Mike: No i think my METSheimers kicked in.
John: Your so lucky, i haven't been diagnosed yet.
by Jayzee123 September 29, 2012