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

significance \signif"icance\, significancy \signif"icancy\,
   n. l. significantia.
   1. the quality or state of being significant.
      1913 webster

   2. that which is signified; meaning; import; as, the
      significance of a nod, of a motion of the hand, or of a
      word or expression.
      1913 webster

   3. importance; moment; weight; consequence.
      1913 webster

            with this brain i must work, in order to give
            significancy and value to the few facts which i
            possess.                              --de quincey.
      1913 webster

[2] : WordNet (r) 2.0

significance
     n 1: the quality of being significant; "do not underestimate the
          significance of nuclear power" ant: insignificance
     2: a meaning that is not expressly stated but can be inferred;
        "the significance of his remark became clear only later";
        "the expectation was spread both by word and by
        implication" syn: import, implication
     3: the message that is intended or expressed or signified;
        "what is the meaning of this sentence"; "the significance
        of a red traffic light"; "the signification of chinese
        characters"; "the import of his announcement was
        ambigtuous" syn: meaning, signification, import
see also:
insignificance import implication meaning signification 

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

135 moby thesaurus words for "significance":
   accent, acceptation, affective meaning, authority, balefulness,
   banefulness, bearing, bodefulness, coloring, concern, concernment,
   connotation, consequence, consequentiality, consideration,
   conspicuousness, content, credit, denotation, direness,
   distinction, doomfulness, drift, effect, elevation, eminence,
   emphasis, essence, exaltation, excellence, expressiveness,
   extension, fatality, fatefulness, force, gist, grammatical meaning,
   grandeur, greatness, high mightiness, high order, high rank, idea,
   impact, implication, import, importance, impression, influence,
   intelligibility, intendment, intension, interest, interpretability,
   lexical meaning, literal meaning, loftiness, magnitude, mark,
   materiality, meaning, meaningfulness, meatiness, merit, message,
   moment, momentousness, nobility, notability, note, ominousness,
   outstandingness, overtone, paramountcy, perfection, pertinence,
   pith, pithiness, point, portent, portentousness,
   practical consequence, precedence, preeminence, pregnancy,
   presagefulness, prestige, primacy, priority, prominence, purport,
   range of meaning, readability, real meaning, reference, referent,
   relation, relevance, scope, self-importance, semantic cluster,
   semantic field, sense, sententiousness, significancy,
   significantness, signification, significatum, signifie,
   sinisterness, span of meaning, spirit, stress, structural meaning,
   sublimity, substance, suggestiveness, sum, sum and substance,
   supereminence, superiority, supremacy, symbolic meaning, tenor,
   totality of associations, transferred meaning, unadorned meaning,
   understanding, undertone, value, vein, virtue, weight, weightiness,
   worth

Significance >> S Words
Significance, definition of term: Significance
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