Definition: A binary relation R for which a R a for all a.

See also symmetric, transitive, irreflexive.

Note: The relation "equals" is reflexive since everything is equal to itself. However the relation "less than" is not reflexive. The relation "likes" is not reflexive either since some people do not like themselves.

Author: PEB

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Entry modified 17 December 2004.
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Cite this as:
Paul E. Black, "reflexive", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 17 December 2004. (accessed TODAY) Available from:

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