# Euler characteristic

Definition from Wiktionary, the free dictionary

## English[edit]

### Noun[edit]

**Euler characteristic** (*plural* **Euler characteristics**)

- (topology, of a topological space) The sum of even-dimensional Betti numbers minus the sum of odd-dimensional ones.
- A polygon or polyhedron's
**Euler characteristic**is just the number of corners minus the number of edges plus the number of faces.

- A polygon or polyhedron's