a relation that is reflexive, symmetrical, and transitive, as equality.
Origin of equivalence relation
First recorded in 1945–50
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
logic maths a relation that is reflexive, symmetric, and transitive: it imposes a partition on its domain of definition so that two elements belong to the same subset if and only if the relation holds between them
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