Phlebotinum is the versatile substance that may be rubbed on anything to cause an effect needed by a plot. Examples include but are not limited to: nanotechnology, magic crystal emanations, pixie dust, and Green Rocks. In essence, it is plot fuel. Without it, the story would grind to an abrupt halt. It's the science that powers the FTL drive on the starship so the characters can get somewhere, it's the magic that hatches the Egg MacGuffin so the protagonist can save an endangered species.