'Extensively' definitions:

Definition of 'extensively'

From: WordNet
adverb
In a widespread way; "oxidation ponds are extensively used for sewage treatment in the Midwest"

Definition of 'Extensively'

From: GCIDE
  • Extensively \Ex*ten"sive*ly\, adv. To a great extent; widely; largely; as, a story is extensively circulated. [1913 Webster]