Pronunciation: /ju╦łnik/ Explain

A mathematical object is unique if there exists exactly one. If a mathematical object is unique, one says, 'There exists one and only one.'


  • The empty set is unique. There is one and only one empty set.
  • In Euclidean geometry two points define a unique line. There is exactly one line defined by the two points.


  1. McAdams, David E.. All Math Words Dictionary, unique. 2nd Classroom edition 20150108-4799968. pg 186. Life is a Story Problem LLC. January 8, 2015. Buy the book

More Information

  • Euclid of Alexandria. Elements. Clark University. 9/6/2018. https://mathcs.clarku.edu/~djoyce/elements/elements.html.

Cite this article as:

McAdams, David E. Unique. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. https://www.allmathwords.org/en/u/unique.html.

Revision History

12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)
12/16/2018: Removed broken links, updated license, implemented new markup. (McAdams, David E.)
8/7/2018: Changed vocabulary links to WORDLINK format. (McAdams, David E.)
9/15/2008: Added 'More Information'. (McAdams, David E.)
7/14/2008: Initial version. (McAdams, David E.)

All Math Words Encyclopedia is a service of Life is a Story Problem LLC.
Copyright © 2018 Life is a Story Problem LLC. All rights reserved.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License