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

significant \signif"icant\, a. l. significans, -antis, p. pr.
   of significare. see signify.
   1. fitted or designed to signify or make known somethingl
      having a meaning; standing as a sign or token; expressive
      or suggestive; as, a significant word or sound; a
      significant look.
      1913 webster

            it was well said of plotinus, that the stars were
            significant, but not efficient.       --sir w.
                                                  raleigh.
      1913 webster

   2. deserving to be considered; important; momentous; as, a
      significant event.
      1913 webster

   significant figures arith., the figures which remain to
      any number, or decimal fraction, after the ciphers at the
      right or left are canceled. thus, the significant figures
      of 25,000, or of .0025, are 25.
      1913 webster
see also:
signify significant figures 

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

significant \signif"icant\, n.
   that which has significance; a sign; a token; a symbol.
   --wordsworth.
   1913 webster

         in dumb significants proclaim your thoughts. --shak.
   1913 webster

[3] : WordNet (r) 2.0

significant
     adj 1: important in effect or meaning; "a significant change in tax
            laws"; "a significant change in the constitution"; "a
            significant contribution"; "significant details";
            "statistically significant" syn: important ant: insignificant
     2: fairly large; "won by a substantial margin" syn: substantial
     3: too closely correlated to be attributed to chance and
        therefore indicating a systematic relation; "the
        interaction effect is significant at the .01 level"; "no
        significant difference was found" ant: nonsignificant
     4: rich in significance or implication; "a meaning look";
        "pregnant with meaning" syn: meaninga, pregnant
see also:
important insignificant substantial nonsignificant meaninga pregnant 

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

174 moby thesaurus words for "significant":
   absolute, adducible, admissible, allegorical, associational,
   attestative, attestive, augural, authentic, based on, big,
   big-league, big-name, big-time, bigwig, bigwigged, certain,
   circumstantial, cogent, compelling, conclusive, connotational,
   connotative, consequential, considerable, conspicuous, convincing,
   critical, cumulative, damning, decisive, definable, demonstrative,
   denominative, denotational, denotative, designative, determinative,
   diagnostic, documentary, documented, double-barreled, earthshaking,
   eloquent, emblematic, evidence, evidential, evidentiary, ex parte,
   exhibitive, expressive, extended, extensional, eye-witness,
   factual, facund, figural, figurative, final, firsthand, forceful,
   forerunning, foreshadowing, foreshowing, foretokening, forewarning,
   founded on, full of meaning, full of point, full of substance,
   grand, great, grounded on, hearsay, heavy with meaning,
   heavyweight, high-powered, historic, identifying, ideographic,
   idiosyncratic, implicative, implicit, important, impressive,
   in the limelight, incontrovertible, index, indicating, indicative,
   indicatory, indisputable, individual, informative, intelligible,
   intensional, interpretable, intuitive, irrefutable, irresistible,
   major, mark, material, meaning, meaningful, meaty, meritorious,
   metaphorical, momentous, monitory, name, naming, notable,
   noteworthy, nuncupative, outstanding, overwhelming, pathognomonic,
   peculiar, pithy, pointed, powerful, precursive, precursory,
   predictive, prefigurative, pregnant, preindicative, premonitory,
   presageful, presaging, presumptive, probative, prognostic,
   prognosticative, prominent, readable, referential, relevant,
   reliable, representative, rich, self-important, semantic, semiotic,
   sententious, sign, signal, signalizing, significative, signifying,
   sound, substantial, substantive, suggestive, superior, sure,
   symbolic, symbolistic, symbological, symptom, symptomatic,
   symptomatologic, telling, to the front, token, transferred,
   typical, valid, valuable, valued, warning, weighty,
   world-shaking

Significant >> S Words
Significant, definition of term: Significant
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Significant Fig >> S Words
Significant Fig, definition of term: Significant Fig
significant+fig_pag1.html