ellipse

(ĭ-lĭpsˈ)

1. A plane curve, especially:
   a. A conic section whose plane is not parallel to the axis, base, or generatrix of the intersected cone.
   b. The locus of points for which the sum of the distances from each point to two fixed points is equal.
2. Ellipsis.

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ellipse

The line running through the foci (F and F₁) of an ellipse is the major axis. The vertices (V and V₁) mark where the major axis intersects the ellipse. The midpoint between the vertices is the center; the line that runs vertically through the center is the minor axis.