"2. a protuberance of flesh above the waistband of a tight pair of trousers."
And while it may have taken Oxford University until 2011 to appreciate the phenomenon, our friends at Creepy Hug have been celebrating Muffin Tops for years. This video is from Chicago Sketchfest 2009, and it also reveals Creepy Hug took notice of Charlie Sheen long before his recent press. They were about 25 years late on Rainbow Bright, however. Enjoy.