crossover

(noun) the interchange of sections between pairing homologous chromosomes during the prophase of meiosis. Synonyms: crossing over.

(noun) a voter who is registered as a member of one political party but who votes in the primary of another party. Synonyms: crossover voter.

(noun) the appropriation of a new style (especially in popular music) by combining elements of different genres in order to appeal to a wider audience. Example: "A jazz-classical crossover album."

(noun) a path (often marked) where something (as a street or railroad) can be crossed to get from one side to the other. Synonyms: crossing, crosswalk.