Source : Webster's Revised Unabridged Dictionary (1913)

Friendliness \Friend"li*ness\, n.
   The condition or quality of being friendly. --Sir P. Sidney.

Source : WordNet®

friendliness
     n 1: a feeling of liking for another person; enjoyment in their
          company [ant: {unfriendliness}]
     2: a friendly disposition [ant: {unfriendliness}]