WordNet sense 1 (the set of elements common to two or more sets):

product, cartesian product

WordNet sense 2 (a point where lines intersect):

intersection point, point of intersection

WordNet sense 3 (a representation of common ground between theories or phenomena):

convergence, overlap

WordNet sense 4 (a junction where one street or road crosses another):

crossing, crossroad, carrefour, crossway