---
tag: T3MBP5GNYF
kind: concept
name: Left-narrow
sources:
  - wikipedia: en:43580500@r1360947732
    locator: Glossary of set theory, section L
    note: adopted
    mention: wikipedia://en/43580500#XW61
    sections: [Summary]
inventory: [SZ48D4JAGG]
---

## Summary

A partially ordered set, (α,≤) in which for all b in α, {c:c∈α∧c≤b} (the down-set of b) is a set.