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parabola
parabola , plane curve consisting of all points equidistant from a given fixed point (focus) and a given fixed line (directrix) (see illustration) . It is the conic section cut by a plane parallel to one of the elements of the cone. The axis of a parabola is the line through the focus perpendicular to the directrix. The vertex is the point at which the axis intersects the curve. The latus rectum is the chord through the focus perpendicular to the axis. Examples of this curve are the path of a projectile and the shape of the cross section of a parallel beam reflector. |
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"parabola." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "parabola." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-parabola.html "parabola." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-parabola.html |
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parabola
parabola A type of curve whose ‘arms’ become parallel as they approach infinity, so that the curve never quite closes in on itself, defined mathematically as a conic section with an eccentricity of 1. It may be regarded as an ellipse in which the two foci are infinitely far apart, and is the limiting case between an ellipse and a hyperbola. Some comets have elliptical orbits that are so extended they are indistinguishable from parabolas.
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"parabola." A Dictionary of Astronomy. 1997. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "parabola." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O80-parabola.html "parabola." A Dictionary of Astronomy. 1997. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-parabola.html |
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parabola
parabola (geom.) plane curve formed by the intersection of a cone by a plane parallel to a side of the cone. XVI. — modL. — Gr. parabolḗ juxtaposition, application; see prec.
So parabolic pert. to parable, metaphorical XVII. — late L. — late Gr.; pert. to a parabola XVIII. parabolical (in both senses) XVI. |
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T. F. HOAD. "parabola." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "parabola." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-parabola.html T. F. HOAD. "parabola." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-parabola.html |
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parabola
parabola Mathematical curve, a conic section traced by a point that moves so that its distance from a fixed point, the focus, is equal to its distance from a fixed straight line, the directrix. It may be formed by cutting a cone parallel to one side. The general equation of a parabola is y = ax2 + bx + c, where a, b, and c are constants.
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"parabola." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "parabola." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-parabola.html "parabola." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-parabola.html |
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Parabola (Journal)
Parabola (Journal)Journal of the Society for the Study of Myth & Tradition, concerned with exploring the inner being through myth and its manifestations. Published quarterly. Address: 656 Broadway, New York, NY 10012. Website: http://www.parabola.org/. Sources:Parabola Online. http://www.parabola.org/. March 8, 2000. |
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"Parabola (Journal)." Encyclopedia of Occultism and Parapsychology. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "Parabola (Journal)." Encyclopedia of Occultism and Parapsychology. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1G2-3403803462.html "Parabola (Journal)." Encyclopedia of Occultism and Parapsychology. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3403803462.html |
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parabola
pa·rab·o·la / pəˈrabələ/ • n. (pl. -las or -lae / -lē/ ) a symmetrical open plane curve formed by the intersection of a cone with a plane parallel to its side. The path of a projectile under the influence of gravity ideally follows a curve of this shape. |
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"parabola." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "parabola." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-parabola.html "parabola." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-parabola.html |
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parabola
parabola. Curve based on a conic section, that is the intersection of a cone with a plane parallel to its side. It resembles a three-centred arch, vertically emphasized.
Bibliography Nicholson (1835) |
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JAMES STEVENS CURL. "parabola." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. JAMES STEVENS CURL. "parabola." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O1-parabola.html JAMES STEVENS CURL. "parabola." A Dictionary of Architecture and Landscape Architecture. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O1-parabola.html |
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