Eccentricity

Origin

eccentric + -ity

Full definition of eccentricity

Noun

1. The quality of being eccentric; any eccentric behaviour.
• 1898, Winston Churchill, The Celebrity Chapter 5, Although the Celebrity was almost impervious to sarcasm, he was now beginning to exhibit visible signs of uneasiness, the consciousness dawning upon him that his eccentricity was not receiving the ovation it merited.
2. (mathematics) The ratio, constant for any particular conic section, of the distance of a point from the focus to its distance from the directrix.
   For an ellipse, the eccentricity is the ratio of the distance from the center to a focus divided by the length of the semi-major axis.