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1. The state or condition of being equivalent; equality.
2. Mathematics An equivalence relation.
3. Logic The relationship that holds for two propositions that are either both true or both false, so that the affirmation of one and the denial of the other results in contradiction.


(ɪˈkwɪvələns) or


1. the state of being equivalent or interchangeable
2. (Logic) maths logic
a. the relationship between two statements, each of which implies the other
b. 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 –(pq) ≡ –p ∨ –q


(ɪˈkwɪv ə ləns or, for 3, ˌi kwəˈveɪ ləns)

1. the state or fact of being equivalent; equality in value, force, significance, etc.
2. an instance of this; an equivalent.
3. the state of having equal chemical valence.
4. Logic.
a. the relation between two propositions such that they are either both true or both false.
b. the relation between two propositions such that each logically implies the other.
5. (of a logical or mathematical relationship) reflexive, symmetrical, and transitive.
[1535–45; < Middle French < Medieval Latin]



neck and neck Even, equal, on a par; abreast, at the same pace. Based on available citations, figurative use of this expression is as old as the literal horse-racing one, both dating from the early 19th century. It still finds frequent application.

Production ran neck and neck in the studios, but the second version … reached the public screen last. (The Times, June, 1955)

nip and tuck So close as to be of uncertain outcome; neck and neck, on a par, even; up in the air, questionable. This chiefly U.S. term is of puzzling origin and inconsistent form, appearing in print in the 1800s as rip and tuck, nip and tack, and nip and chuck, before assuming its present nip and tuck. Its original restriction to contexts describing close contests, usually athletic, lends credence to the claim that it originated as a wrestling term (Barrère and Leland, Dictionary of Slang, 1890). The expression is now employed in much broader contexts, indicative of any kind of uncertainty.

It is nip and tuck whether such a last great achievement of the bipartisan foreign policy can be ratified before … the Presidential race. (The Economist, May, 1948)

ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.equivalence - a state of being essentially equal or equivalent; equally balanced; "on a par with the best"
status, position - the relative position or standing of things or especially persons in a society; "he had the status of a minor"; "the novel attained the status of a classic"; "atheists do not enjoy a favorable position in American life"
egalite, egality - social and political equality; "egality represents an extreme leveling of society"
tie - equality of score in a contest
2.equivalence - essential equality and interchangeability
equality - the quality of being the same in quantity or measure or value or status
parity - functional equality
nonequivalence - not interchangeable
3.equivalence - qualities that are comparableequivalence - qualities that are comparable; "no comparison between the two books"; "beyond compare"
alikeness, likeness, similitude - similarity in appearance or character or nature between persons or things; "man created God in his own likeness"



The state of being equivalent:


[ɪˈkwɪvələns] Nequivalencia f


[ɪˈkwɪvələns] néquivalence f


nÄquivalenz f, → Entsprechung f


[ɪˈkwɪvələns] nequivalenza


n equivalencia
References in classic literature ?
And thus, O circular philosopher, I hear some reader exclaim, you have arrived at a fine Pyrrhonism, at an equivalence and indifferency of all actions, and would fain teach us that if we are true, forsooth, our crimes may be lively stones out of which we shall construct the temple of the true God!
Procedures used to study stimulus equivalence involve the establishment of sets of conditional discriminations and the assessment of stimulus equivalence within these stimulus classes.
Here the number one cylinder of four inline cylinders in a gasoline engine is used as a "dedicated cylinder" to operate in the rich condition with an equivalence ratio above 1.
Eligibility of third-country jurisdictions for endorsement and equivalence
LAHORE -- A Lahore High Court division bench Thursday restored Punjab University's (PU) Equivalence department while suspending a single bench order.
i] (X) is a partition of X and every Fi (X) is an equivalence class.
Muscat, July 13 (ONA) The Ministry of Higher Education today hosted the 11th meeting of the GCC Technical Team of the Higher Education Certificate Equivalence in the presence of officials and specialists from the GCC Secretariat General and the educational qualifications equivalence departments in the GCC countries.
com Vocational certificates, such as training courses and high school degrees, will not be eligible for equivalence certificates.
Some countries are eyeing equivalence as a way to develop a consistent, risk-based solvency regime and reporting requirements for the insurance sector.
p(e)] denotes the constant path at p(e); this map is a homotopy equivalence.
This paper, which is based on Nida's equivalence translation theory, discusses the process involved in translation as a mathematical problem.
This phenomenon has been studied on many occasions within the Experimental Analysis of Behavior, beginning with Sidman's discoveries in 1971 (see Garcia & Benjumea, 2001) and continuing with those of other authors within the framework of equivalence classes.