hardheartedly vs indifferently

hardheartedly

adv
  • In a hardhearted manner. 

indifferently

adv
  • Tolerably; passably. 

  • Without distinction; impartially, objectively. 

  • Without great care; without sufficient attention or thought. 

How often have the words hardheartedly and indifferently occurred in a corpus of books? (source: Google Ngram Viewer )