Source : Webster's Revised Unabridged Dictionary (1913)

Proclivity \Pro*cliv"i*ty\, n. [L. proclivitas: cf. F.
   proclivit['e].]
   1. Inclination; propensity; proneness; tendency. ``A
      proclivity to steal.'' --Abp. Bramhall.

   2. Readiness; facility; aptitude.

            He had such a dexterous proclivity as his teachers
            were fain to restrain his forwardness. --Sir H.
                                                  Wotton.

Source : WordNet®

proclivity
     n : a natural inclination; "he has a proclivity for
         exaggeration" [syn: {propensity}, {leaning}]