Noun

• S: (n) leaning, propensity, tendency (an inclination to do something) "he felt leanings toward frivolity"
• S: (n) proclivity, propensity, leaning (a natural inclination) "he has a proclivity for exaggeration"
• S: (n) aptness, propensity (a disposition to behave in a certain way) "the aptness of iron to rust"; "the propensity of disease to spread"