look up any word, like sparkle pony:

1 definition by Levstrong

 
1.
A fanfiction in which several fandoms interact with one another.

Cross-overs largely involve time travel and interdimensional travel to meld two different fandoms.
I was confused when Dr. Gregory House was treating Harry Potter's illness, but I soon realized that I was merely reading a cross-over.
by Levstrong November 13, 2007