a somewhat paraphrased definition: when very complicated, intelligent, complex, dense, or otherwise hard to understand material is stated, followed by someone explaining in very layman's terms (usually with a spark of eureka wonder). Example: Captain: "We'll have to fire the self-gravity-having-gravitron-thingy into the nucleus. Then it'll have to penetrate the outer level and begin moving in a counter clockwise orbit. If it can move at a fast enough speed, it will create an inner vortex." Ensign: "Like a spoon stirring a cup of coffee!" This happens on just about every episode of Star Trek, and just about every outer space show for that matter.
"Your current frequencies of understanding outweigh that which has been given for you to understand." Saul Williams