Nisbetitis Share definition Flag (Also known as HCS - Horse Cock Syndrome) A rare condition whereby a male penis is exessively large, and near superhuman. Hey, I heard that kids got Nisbetitis. Nisbetitis by Josiah Escobar January 16, 2006 0 0 Get merch Get the Nisbetitis mug. Buy Now — $32.95 See more merch