Definition of: eccentricity

(ek′sen·tris′ə·tē) noun plural ·ties
1. The state or quality of being eccentric; oddity.
2. An odd or capricious act.
3. The distance between the centers of two eccentric circles or objects.
4. The condition or quality of being eccentric.
5. Math. The ratio of the distance between the focus and the center of a conic to half of its transverse axis; formerly, the distance itself. Also spelled excentricity.