---
tag: 3GZHPRAFWS
kind: concept
name: Binding number
sources:
  - wikipedia: en:325802@r1373839425
    locator: Glossary of graph theory, section B
    note: adopted
    mention: wikipedia://en/325802#81CU
    sections: [Summary]
inventory: [AKT0D9SR4E]
---

## Summary

The smallest possible ratio of the number of neighbors of a proper subset of vertices to the size of the subset.