The Collaborative International Dictionary of English v.0.48:

Rapacity \Ra*pac"i*ty\ (r[.a]*p[a^]s"[i^]*t[y^]), n. [L.
   rapacitas: cf. F. rapacit['e]. See Rapacious.]
   1. The quality of being rapacious; rapaciousness;
      ravenousness; as, the rapacity of pirates; the rapacity of
      wolves.
      [1913 Webster]

   2. The act or practice of extorting or exacting by oppressive
      injustice; exorbitant greediness of gain. "The rapacity of
      some ages." --Sprat.
      [1913 Webster]

WordNet (r) 3.0 (2006):

rapacity
    n 1: extreme gluttony [syn: edacity, esurience,
         rapaciousness, rapacity, voracity, voraciousness]
    2: reprehensible acquisitiveness; insatiable desire for wealth
       (personified as one of the deadly sins) [syn: avarice,
       greed, covetousness, rapacity, avaritia]

The Devil's Dictionary (1881-1906):

RAPACITY, n.  Providence without industry.  The thrift of power.