pro·cliv·i·ty 
(prō-klĭvĭ-tē)
(prō-klĭvĭ-tē)n. pl. pro·cliv·i·ties
A natural propensity or inclination; a predisposition: a proclivity for exaggeration; a proclivity to complain.
[Latin prōclīvitās, from prōclīvis, inclined : prō-, forward; see PRO-1 + clīvus, slope; see klei- in the Appendix of Indo-European roots.]