binary relation


Definition: A relation between exactly two items at a time, such as "greater than" (>), "not equal to" (≠), "proper subset of" (⊂), or "is connected to" (has an edge to) for vertices of a graph.

Generalization (I am a kind of ...)

Specialization (... is a kind of me.)

See also binary function, reflexive, symmetric, transitive, antisymmetric, irreflexive.

Note: One may think of a binary relation as a binary function whose range is {true, false}. For example since 3 > 2, GreaterThan(3, 2) = true.

Author: PEB

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If you have suggestions, corrections, or comments, please get in touch with Paul E. Black.

Entry modified 15 October 2004.
HTML page formatted Fri Mar 25 16:20:34 2011.

Cite this as:
Paul E. Black, "binary relation", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 15 October 2004. (accessed TODAY) Available from:

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