Triskaidekaphobia - what does it mean?

In Paternity, one of the characters (who happens to have been born on a Friday the 13) seems to experience bouts of bad luck. In chapter 33, as she is about to turn thirteen, she encounters the word "triskaidekaphobia" and a revelation of sorts ensues. If you're curious about the origins of the word, triskaidekaphobia, just click on the link.