cylon toast means: Source: BIG BANG THEORY. Cylons, a fictional robot race and arch-enemy of humans are the Cylons. Two forms of Cylons are seen in the Battlestar Galactica series: metal-skinned “Centurions”, robotic “Centurions”, and human-looking, “Skin jobs”. Many of the Cylons have evolved to humanoid forms, but they’re still called “toasters” in the eyes of humans. Sheldon has a limited edition toaster which imprints the head a Cylon Centurion on the bread. In The Cornhusker Vortex, he attempts to create enough Cylon toast to “destroy all human toasts” on the Battlestar Galactica. Sheldon is an actor in BIG BANG THEORY. (in Community Dictionary, added by Minutious)