ECCENTRIC'ITY, n. Deviation from a center.

1. The state of having a center different from that of another circle.

2. In astronomy, the distance of the center of a planet's orbit from the center of the sun; that is, the distance between the center of an ellipsis and its focus.

3. Departure or deviation from that which is stated, regular or usual; as the eccentricity of a man's genius or conduct.

4. Excursion from the proper sphere.