'Extensiveness' definitions:

Definition of 'extensiveness'

From: WordNet
noun
Large or extensive in breadth or importance or comprehensiveness; "the might have repercussions of unimaginable largeness"; "the very extensiveness of his power was a temptation to abuse it" [syn: largeness, extensiveness]

Definition of 'Extensiveness'

From: GCIDE
  • Extensiveness \Ex*ten"sive*ness\, n. The state of being extensive; wideness; largeness; extent; diffusiveness. [1913 Webster]