- a plane curve such that the sums of the distances of each point in its periphery from two fixed points, the foci, are equal. It is a conic section formed by the intersection of a right circular cone by a plane that cuts the axis and the surface of the cone. Typical equation: (x2/a2) + (y2/b2) = 1. If a = b the ellipse is a circle.
Origin of ellipse
Examples from the Web for ellipse
A hole, though shaped like an ellipse, in which this well-hung stud had placed it would look as if a compass traced it.Read This and Blush: Naughty Medieval French Tales
June 13, 2013
On Dec. 18, a triumphant Johnson appeared on the Ellipse outside the White House to light the national Christmas tree.The Mad Men Era: When Hope Was Cheap
March 19, 2012
These marks will then represent the diameter of the ellipse across its major axis.Practical Mechanics for Boys
J. S. Zerbe
It is not allowed to move exactly in an ellipse, nor is the earth exactly in the focus.
Now it is remarkable that this apparent path is still an ellipse.
These points are your centers for scribing the long sides of the ellipse.Carpentry for Boys
J. S. Zerbe
The other two being intersected at an angle, will each be an ellipse.The Theory and Practice of Perspective
George Adolphus Storey
- a closed conic section shaped like a flattened circle and formed by an inclined plane that does not cut the base of the cone. Standard equation x ²/ a ² + y ²/ b ² = 1, where 2 a and 2 b are the lengths of the major and minor axes. Area: π ab
Word Origin and History for ellipse
1753, from French ellipse (17c.), from Latin ellipsis "ellipse," also, "a falling short, deficit," from Greek elleipsis (see ellipsis). So called because the conic section of the cutting plane makes a smaller angle with the base than does the side of the cone, hence, a "falling short." First applied by Apollonius of Perga (3c. B.C.E.).
- A closed, symmetric curve shaped like an oval, which can be formed by intersecting a cone with a plane that is not parallel or perpendicular to the cone's base. The sum of the distances of any point on an ellipse from two fixed points (called the foci) remains constant no matter where the point is on the curve.
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.