Proneness

having a natural inclination or tendency to something; disposed; liable

to be prone to anger.

having the front or ventral part downward; lying face downward.

lying flat; prostrate.

having a downward direction or slope.

having the palm downward, as the hand.

noun

bias , cast , disposition , leaning , partiality , penchant , predilection , predisposition , proclivity , propensity , squint , tendency , trend , turn