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

vastness \vast"ness\, n.
   the quality or state of being vast.
   1913 webster

[2] : WordNet (r) 2.0

vastness
     n : unusual largeness in size or extent syn: enormousness, grandness,
          greatness, immenseness, immensity, sizeableness
see also:
enormousness grandness greatness immenseness immensity sizeableness 

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

31 moby thesaurus words for "vastness":
   ampleness, amplitude, boundlessness, bulk, enormity, enormousness,
   expanse, formidableness, fullness, gigantism, grandeur, grandness,
   great scope, greatness, hugeness, immensity, infinity, intensity,
   largeness, magnitude, might, mightiness, monstrosity,
   monstrousness, muchness, plenitude, power, prodigiousness,
   strength, stupendousness, tremendousness

Vastness >> V Words
Vastness, definition of term: Vastness
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