WordNet sense 1 (a shallow area in a stream that can be forded):

ford

WordNet sense 2 (a junction where one street or road crosses another):

crossroad, intersection, carrefour, crossway

WordNet sense 3 (a path (often marked) where something (as a street or railroad) can be crossed to get from one side to the other):

crossover, crosswalk

WordNet sense 4 ((genetics) the act of mixing different species or varieties of animals or plants and thus to produce hybrids):

cross, hybridization, crossbreeding, hybridisation, hybridizing, interbreeding