Source : Webster's Revised Unabridged Dictionary (1913)

Lavishness \Lav"ish*ness\, n.
   The quality or state of being lavish.

Source : WordNet®

lavishness
     n 1: the quality possessed by something that is excessively
          expensive [syn: {luxury}, {sumptuosity}, {sumptuousness}]
     2: excessive spending [syn: {extravagance}, {prodigality}, {highlife},
         {high life}]