node
unit connected by edges with other units in a graph, in graph theory
universal vertex
vertex of an undirected graph that is adjacent to all other vertices of the graph. It may also be called a dominating vertex, as it forms a one-element dominating set in the graph
source vertex
graph vertex with no inward-directed edges, making it the origin of each of its outgoing edges
child vertex
direct descendent in a rooted tree
cut vertex
graph vertex whose removal increases the number of connected components
sink vertex
graph vertex with no outward-directed edges, making it the end of each of its incoming edges
ground in electronics
common ground network in electronic circuits and systems, which serves as a zero voltage reference
node
intersection of three or more electrical cunductors
isolated vertex
graph vertex that is not connected with any other vertex
root node
chosen vertex in a graph
inner vertex
in graph theory, non-leaf vertex of a tree