- The definition of an ellipse is a path taken or a shape that results when a flat plane intersects a cone in a direction which is not parallel to the base of the cone.
An example of an ellipse are the rings of Saturn.
The dark circle within the cone is an ellipse.Licensed from iStockPhoto
Origin: Modern Latin ellipsis ; from Classical Greek elleipsis, a defect, ellipse ; from elleipein, to fall short ; from en-, inch(es) plush leipein, to leave (see loan): so named from falling short of a perfect circle
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- 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.
Origin: French, from Latin ellīpsis, from Greek elleipsis, a falling short, ellipse, from elleipein, to fall short (from the relationship between the line joining the vertices of a conic and the line through the focus and parallel to the directrix of a conic) : en-, in; see en-2 + leipein, to leave; see leikw- in Indo-European roots.
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.
ellipse - Cultural Definition
In geometry, a curve traced out by a point that is required to move so that the sum of its distances from two fixed points (called foci) remains constant. If the foci are identical with each other, the ellipse is a circle; if the two foci are distinct from each other, the ellipse looks like a squashed or elongated circle.
ellipse - Science Definition
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