1. strange and unconventional behavior

Definition categories: attribute, strangeness, unfamiliarity

2. (geometry) a ratio describing the shape of a conic section; the ratio of the distance between the foci to the length of the major axis

- a circle is an ellipse with zero eccentricity

Definition categories: shape, ratio

3. a circularity that has a different center or deviates from a circular path

Definition categories: attribute, circularity

Sentences with eccentricity as a noun:

- 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.