GraphUnion

GraphUnion[g1,g2] gives the graph union of the graphs g1 and g2.

GraphUnion[g1,g2,…] gives the graph union of g1, g2, ….

GraphUnion[{v->w,…},…] uses rules v->w to specify the graph g.

Examples

GraphUnion[CycleGraph[3], CycleGraph[4]]

Please visit the official Wolfram Language Reference for more details.