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

commonness \com"monness\, n.
   1. state or quality of being common or usual; as, the
      commonness of sunlight.
      1913 webster

   2. triteness; meanness.
      1913 webster

[2] : WordNet (r) 2.0

commonness
     n 1: the state of being that is commonly observed syn: expectedness
     2: the quality of lacking taste and refinement syn: coarseness,
         grossness, vulgarity, vulgarism, raunch
     3: ordinariness as a consequence of being frequent and
        commonplace syn: commonplaceness, everydayness ant:
         uncommonness
     4: sharing of common attributes syn: commonality ant: individuality
see also:
expectedness coarseness grossness vulgarity vulgarism raunch 
commonplaceness everydayness uncommonness commonality individuality 

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

87 moby thesaurus words for "commonness":
   attic simplicity, accustomedness, averageness, banality, banalness,
   baseness, chasteness, classical purity, cliche, coarseness,
   common occurrence, commonality, commonplaceness, confirmedness,
   conventionality, corniness, currency, customariness, dullness,
   extensiveness, familiarness, fixedness, flatness, fourth-rateness,
   frequence, frequency, fustiness, garden variety, generality,
   habitualness, hackneyedness, homeliness, humbleness, ignobility,
   incidence, inferiority, inferiorness, insipidness, inveteracy,
   inveterateness, lowliness, lowness, matter-of-factness, meanness,
   mustiness, normality, oftenness, ordinariness, plainness,
   platitudinousness, plebeianism, poorness, prevalence, prosaicism,
   prosaicness, prosaism, prosiness, purity, rampantness, reign,
   relative incidence, rifeness, routineness, run, second-rateness,
   settledness, simpleness, simplicity, squareness, staleness,
   standardness, sweepingness, third-rateness, triteness,
   unembellishedness, unexceptionality, unidealism, unimaginativeness,
   unnoteworthiness, unoriginality, unpoeticalness, unremarkableness,
   unromanticism, usualness, vapidity, widespreadness, wontedness

Commonness >> C Words
Commonness, definition of term: Commonness
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