eccentricity

n.; pl. Eccentricities [ Cf. F. excentricité. ] 1. The state of being eccentric; deviation from the customary line of conduct; oddity. [ 1913 Webster ]

2. (Math.) The ratio of the distance between the center and the focus of an ellipse or hyperbola to its semi-transverse axis. [ 1913 Webster ]

3. (Astron.) The ratio of the distance of the center of the orbit of a heavenly body from the center of the body round which it revolves to the semi-transverse axis of the orbit. [ 1913 Webster ]

4. (Mech.) The distance of the center of figure of a body, as of an eccentric, from an axis about which it turns; the throw. [ 1913 Webster ]