Pronunciation: /yuˈnik/ ?

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. unique. http://wordnet.princeton.edu/. WordNet. Princeton University. (Accessed: 2011-01-08). http://wordnetweb.princeton.edu/perl/webwn?s=unique&sub=Search+WordNet&o2=&o0=1&o7=&o5=&o1=1&o6=&o4=&o3=&h=.

Cite this article as:

Unique. 2008-09-15. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/u/unique.html.


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Revision History

2008-09-15: Added 'More Information' (McAdams, David.)
2008-07-14: Initial version (McAdams, David.)

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