[1] : The Collaborative International Dictionary of English v.0.48

equivalence \equiv"alence\, v. t.
   to be equivalent or equal to; to counterbalance. r. --sir
   t. browne.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

equivalence \equiv"alence\ -ekwi^v".alens, n. cf.
   f. 'equivalence, ll. aequivalentia.
   1. the condition of being equivalent or equal; equality of
      worth, value, signification, or force; as, an equivalence
      of definitions.
      1913 webster

   2. equal power or force; equivalent amount.
      1913 webster

   3. chem.
      a the quantity of the combining power of an atom,
          expressed in hydrogen units; the number of hydrogen
          atoms can combine with, or be exchanged for; valency.
          see valence.
      b the degree of combining power as determined by
          relative weight. see equivalent, n., 2. r.
          1913 webster
see also:
valence equivalent 

[3] : WordNet (r) 2.0

equivalence
     n 1: a state of being essentially equal or equivalent; equally
          balanced; "on a par with the best" syn: equality, equation,
           par
     2: essential equality and interchangeability ant: nonequivalence
     3: qualities that are comparable; "no comparison between the
        two books"; "beyond compare" syn: comparison, compare,
         comparability
see also:
equality equation par nonequivalence comparison compare 
comparability 

[4] : Moby Thesaurus II by Grady Ward, 1.0

97 moby thesaurus words for "equivalence":
   accord, accordance, affinity, agreement, analogousness, assent,
   balance, chorus, coequality, coextension, coherence, coincidence,
   commensurability, communion, community, comparability,
   comparableness, comparativeness, compatibility, concert, concord,
   concordance, conformance, conformation, conformity, congeniality,
   congruence, congruency, congruity, consistency, consonance,
   consort, cooperation, corelation, correlation, correlativism,
   correlativity, correspondence, equality, equation, equilibrium,
   equipoise, equipollence, equiponderance, equity, equivalency,
   evenness, harmony, homogeneity, homoousia, identity,
   indistinguishability, intersection, inverse proportion,
   inverse ratio, inverse relationship, justice, levelness, likeness,
   mutuality, no difference, oneness, overlap, par, parallelism,
   parity, peace, poise, proportion, proportionability,
   proportionality, rapport, ratio, reciprocality, reciprocation,
   reciprocity, relativity, sameness, self-consistency, self-identity,
   selfhood, selfness, selfsameness, similarity, symmetry, sync,
   synchronism, synonymity, synonymousness, synonymy, tally, timing,
   uniformity, union, unison, unisonance, unity

Equivalence >> E Words
Equivalence, definition of term: Equivalence
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