Crossover

Noun

 * 1) A place where one thing crosses over another.
 * 2) The means by which the crossing is made.
 * 3) (genetics) the result of the exchange of genetic material during meiosis.
 * 4) A blend of multiple styles of music, intended to appeal to a wider audience.
 * 5) An automobile that is a mix of two kinds of automobiles, i.e. the Pontiac Torrent.
 * 6)  A pair of switches and a short, diagonal length of track which together connect two parallel tracks and allow passage between them.
 * 7) A piece of fiction that borrows elements from two or more fictional universes.