gratitude

from WordNet (r) 3.0 (2006)

gratitude
    n 1: a feeling of thankfulness and appreciation; "he was
         overwhelmed with gratitude for their help" [ant:
         {ingratitude}, {ungratefulness}]

from The Collaborative International Dictionary of English v.0.48

Gratitude \Grat"i*tude\, n. [F. gratitude, LL. gratitudo, from
   gratus agreeable, grateful. See {Grate}, a.]
   The state of being grateful; warm and friendly feeling toward
   a benefactor; kindness awakened by a favor received;
   thankfulness.
   [1913 Webster]

         The debt immense of endless gratitude.   --Milton.
   [1913 Webster]