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ellipse
ellipse closed plane curve consisting of all points for which the sum of the distances between a point on the curve and two fixed points (foci) is the same. It is the conic section formed by a plane cutting all the elements of the cone in the same nappe. The center of an ellipse is the point halfway between its foci. The major axis is the chord that passes through the foci. The minor axis is the chord that passes through the center perpendicular to the major axis. The latus rectum is the chord through either focus perpendicular to the major axis. The vertices are the two points of intersection of the major axis with the curve. The eccentricity of an ellipse, a ratio of two lengths, is a measure of its flatness; it is the distance from the center to either focus divided by the distance from the center to either vertex. The circle may be considered an ellipse of eccentricity zero, i.e., one in which the center and the two foci all coincide. |
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"ellipse." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "ellipse." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-ellipse.html "ellipse." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-ellipse.html |
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ellipse
ellipse A closed curve like a flattened circle. The orbits of most celestial bodies are ellipses; the body being orbited lies at one focus of the ellipse. The longest diameter of an ellipse is termed its major axis, and the shortest diameter is the minor axis. Half the major axis is the semimajor axis, usually denoted by the letter a; the semiminor axis (half the minor axis) is usually denoted by b. The distance between the two foci of an ellipse divided by the length of the major axis is the ellipse's eccentricity, e. The eccentricity defines the shape of the ellipse, the ellipse being a circle when e = 0. When e is almost 1, the ellipse is long and narrow. For example, Halley's Comet follows an orbit for which e = 0.967.
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"ellipse." A Dictionary of Astronomy. 1997. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "ellipse." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O80-ellipse.html "ellipse." A Dictionary of Astronomy. 1997. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-ellipse.html |
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ellipse
ellipse Conic section formed by cutting a right circular cone with a plane inclined at such an angle that the plane does not intersect the base of the cone. When the intersecting plane is parallel to the base, the conic section is a circle. In rectangular Cartesian coordinates its standard equation is x2/a2 + y2/b2 = 1. Most planetary orbits are ellipses.
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"ellipse." World Encyclopedia. 2005. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "ellipse." World Encyclopedia. 2005. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O142-ellipse.html "ellipse." World Encyclopedia. 2005. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-ellipse.html |
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ellipse
el·lipse
/ iˈlips/
•
n.
a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points (the foci) is constant, or resulting when a cone is cut by an oblique plane that does not intersect the base.
ellipse |
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"ellipse." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "ellipse." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-ellipse.html "ellipse." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-ellipse.html |
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ellipse
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JAMES STEVENS CURL. "ellipse." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. JAMES STEVENS CURL. "ellipse." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O1-ellipse.html JAMES STEVENS CURL. "ellipse." A Dictionary of Architecture and Landscape Architecture. 2000. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O1-ellipse.html |
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ellipse
ellipse XVIII. — F. — L. ell¯psis (see next).
Hence ellipsoid XVIII. |
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T. F. HOAD. "ellipse." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "ellipse." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O27-ellipse.html T. F. HOAD. "ellipse." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-ellipse.html |
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ellipse
ellipse
•apse, collapse, craps, elapse, lapse, perhaps, schnapps
•prolapse • synapse • Lesseps
•quadriceps
•biceps, triceps
•forceps
•traipse, trapes
•jackanapes • Pepys
•Chips, eclipse, ellipse, thrips
•Phillips • apocalypse
•amidships, midships
•cripes, Stars and Stripes
•copse • Cheops • Pelops • Cyclops
•triceratops • corpse • Stopes
•oops, whoops
•turps • mumps • goosebumps
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"ellipse." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "ellipse." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O233-ellipse.html "ellipse." Oxford Dictionary of Rhymes. 2007. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-ellipse.html |
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