In the Christian tradition, Epiphany (ə-PIF-ə-nee) is a festival celebrating Christ's appearance to the Gentiles, observed every year on January 6. From the Christian sense we get an additional religious sense, "the appearance of a god or deity" and the more common modern usage, a noun meaning "a sudden revelation." There's nothing religious about most epiphanies these days — your "Eureka!" moment could come when you realize that you're in the wrong line of work and you need to quit your job to join the circus.

Christians believe that on the Epiphany, the infant Christ was visited by three kings bearing gifts. It's also referred to as Twelfth Day, Three Kings Day, or Epiphany of Our Lord. It's celebrated differently around the world and can include the baking of a "king cake," gift giving, singing, and grand parades. Epiphany with a lower-case "e" means a moment of realization or understanding — like a magical "aha" moment, where you are one of those wise men.