I love this word (or two words) just because it's awesome... The definition is defined in different ways, but it was first invented in Kurt Vonnegut's "The Sirens of Titan." It's totally Doctor Who-ish - the definition is this:
Noun; A point in space where, upon a person entering it, that person's existence in space-time ceases to be linear, becoming discrete. This means that a person that has entered a chronosynclastic infundibulum exists at multiple points and lines in space-time. For example, such a person could exist at all points in time in one place and also appear at another point for five minutes. A prime example of a victim was William Niles Rumfoord, (From 'Sirens of Titan') who would appear on Earth every 59 days for one hour. He also would appear on Mars, Mercury, Beatlegeuse, and Titan. He was able to see what was happening in different places at all times, but was not able to know everything. The sensation has been described as "being everywhere at once".