# Definition:Circuit

## Definition

A **circuit** is a closed trail with at least one edge.

The set of vertices and edges which go to make up a circuit form a subgraph.

This subgraph itself is also referred to as a **circuit**.

## Also see

## Sources

- 1977: Gary Chartrand:
*Introductory Graph Theory*... (previous) ... (next): $\S 2.3$: Connected Graphs