[ih-kwiv-uh-luh ns or for 3, ee-kwuh-vey-luh ns]
noun Also equivalency (for defs 1, 2).
the state or fact of being equivalent; equality in value, force, significance, etc.
an instance of this; an equivalent.
Chemistry. the quality of having equal valence.
- Also called material implication.the relation between two propositions such that the second is not false when the first is true.
- Also called material equivalence.the relation between two propositions such that they are either both true or both false.
- the relation between two propositions such that each logically implies the other.
(of a logical or mathematical relationship) reflexive, symmetrical, and transitive.
Origin of equivalence
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the state of being equivalent or interchangeable
- the relationship between two statements, each of which implies the other
- Also called: biconditionalthe binary truth-function that takes the value true when both component sentences are true or when both are false, corresponding to English if and only if . Symbol: ≡ or ↔, as in –(p ∧ q) ≡ – p ∨ – q
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
1540s, from French équivalence, from Medieval Latin aequivalentia, from aequivalentem (see equivalent). Related: Equivalency (1530s).
Online Etymology Dictionary, © 2010 Douglas Harper