in·cli·na·tion 
(ĭn′klə-nāshən)
(ĭn′klə-nāshən)n.
1. The act of inclining or the state of being inclined; a bend or tilt: The inclination of the child's head suggested sleep.
2.
a. A deviation or the degree of deviation from the horizontal or vertical; a slant: the steep inclination of a roof.
b. The angle between two lines or planes: the inclination of the comet's orbit with respect to that of Earth.
c. An inclined surface; a slope.
3.
a. A characteristic disposition or tendency to act in a certain way; a propensity: "I shall indulge the inclination so natural in old men, to be talking of themselves" (Benjamin Franklin).
b. A preference or liking: his musical inclinations.