Steve Tyler Mouth 

To have an insanely huge mouth, such as Steve Tyler, the lead singer of Aerosmith. Could also be called Steve Tyler Mouth Syndrome, for the unfortunate people who have to be as fugly as Steve Tyler.

Guy 1: Dude, when I was a kid, I went to an Aerosmith concert, and when Steve Tyler opened his mouth, you could see his effin' stomach, I swear to God.
Guy 2: Don't be insultin' Steve, man, you're just trying to take away from everyone's attention that you have Steve Tyler Mouth yourself, dickweed.

Steve Tyler Mouth by Spatchmo December 28, 2008