the state of being equivalent or interchangeable the relationship between two statements, each of which implies the other - Also called: biconditional
the 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
WordReference Random House Learner's Dictionary of American English © 2026
e•qui•val•ence /ɪˈkwɪvələns/USA pronunciation n.
WordReference Random House Unabridged Dictionary of American English © 2026- the act or condition of being the same or equal in value, measure, force: [uncountable]demanding equivalence in treatment.[countable]An equivalence was found between the two chemical reactions.
e•quiv•a•lence
(i kwiv′ə ləns or, for 3, ē′kwə vā′ləns),USA pronunciation n.
adj.
- the state or fact of being equivalent;
equality in value, force, significance, etc. - an instance of this;
an equivalent. - Chemistrythe quality of having equal valence.
- Philosophy, Mathematics[Logic, Math.]
- 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.
adj.
- Mathematics, Philosophy(of a logical or mathematical relationship) reflexive, symmetrical, and transitive.
- Medieval Latin aequivalentia, equivalent. to Latin aequivalent- equivalent + -ia -ia; see -ence
- Middle French
- 1535–45
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