# Poincaré conjecture

> English word · Proper noun

## Definitions
1. The theorem that the only simply connected, closed 3-dimensional manifold is a sphere.

## Etymology
Originally conjectured by Henri Poincaré.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/poincare-conjecture