In a graph , two graph vertices are adjacent,
or neighboring, if they are joined by a graph edge.
Each is then called a neighbor of the other.
Adjacent Vertices
See also
Graph, Graph Edge, Graph Neighborhood, Graph Vertex, NeighborExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Adjacent Vertices." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/AdjacentVertices.html