---
tag: 01CGSJ0GNQ
kind: concept
name: Well-order
aliases: [well-ordering, well-ordered-set]
msc: [06A05]
sources:
  - url: https://en.wikipedia.org/wiki/Well-order
    locator: lead section
same_as:
  wikidata: Q659746
  wikipedia: Well-order
---

## Summary

A well-order is a total order in which each nonempty subset has a least element.