adverb (r)

• in an insane manner(adv.all)

  Example:
  She behaved insanely.
  

  Synonym:
  crazily, dementedly, madly
  Antonym:
  sanely
  

  source: wordnet30
• (used as intensives) extremely(adv.all)

  Example:
  Insanely jealous.
  

  Synonym:
  deadly, deucedly, devilishly, madly
  

  source: wordnet30
• Without reason; madly; foolishly.(adverb)

  source: webster1913