noun
1. A theory that there is a mirror universe and when one makes a decision in this universe, an alternate 'you' in the other universe makes the opposite decision.
EX. In a parallel universe, Squirtle was my starter Pokémon, in Pokémon Blue Version, instead of Charmander. In that Universe, my team when I played against the Elite Four was Blastoise, Alakazam, Jolteon, Arcanine, Snorlax, and Articuno. I got Alakazam by trading a Machoke for a Kadabra. In that universe, I traded my Pokémon, and made different friends. From that moment, my life begins to change more and more from this one until I'm an actor on the Disney Channel show "What's That Smell?", then star in the second Transformers movie, before winding up crashing a tractor into an Alaskan ice fissure with Lindsay Lohan and being eaten alive by a Grizzly-Polar Bear hybrid.
I guess it's a good thing I chose Charmander?