/kohn/, n., v., coned, coning.
1. Geom.
a. a solid whose surface is generated by a line passing through a fixed point and a fixed plane curve not containing the point, consisting of two equal sections joined at a vertex.
b. a plane surface resembling the cross section of a solid cone.
2. anything shaped like a cone: sawdust piled up in a great cone; the cone of a volcano.
4. Bot.
a. the more or less conical multiple fruit of the pine, fir, etc., consisting of overlapping or valvate scales bearing naked ovules or seeds; a strobile.
b. a similar fruit, as in cycads or club mosses.
5. Anat. one of the cone-shaped cells in the retina of the eye, sensitive to color and intensity of light. Cf. rod (def. 17).
6. one of a series of cone-shaped markers placed along a road, as around an area of highway construction, esp. to exclude or divert motor vehicles.
7. (in a taper thread screw or bevel gear) an imaginary cone or frustum of a cone concentric to the axis and defining the pitch surface or one of the extremities of the threads or teeth.
8. Ceram. See pyrometric cone.
9. to shape like a cone or a segment of a cone.
[1480-90; < L conus < Gk kônos pine-cone, cone-shaped figure; akin to HONE1]

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In botany, a mass of scales or bracts, usually ovate, containing the reproductive organs of certain non-flowering plants.

A distinguishing feature of pines and other conifers, the cone is roughly analogous to the flower of other plants. Cones (strobili) are also found on club mosses and horsetails.

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      in mathematics, the surface traced by a moving straight line (the generatrix) that always passes through a fixed point (the vertex). The path, to be definite, is directed by some closed plane curve (the directrix), along which the line always glides. In a right circular cone, the directrix is a circle, and the cone is a surface of revolution. The axis of this cone is a line through the vertex and the centre of the circle, the line being perpendicular to the plane of the circle. In an oblique circular cone, the angle that the axis makes with the circle is other than 90°. The directrix of a cone need not be a circle; and if the cone is right, planes parallel to the plane of the directrix produce intersections with the cone that take the shape, but not the size, of the directrix. For such a plane, if the directrix is an ellipse, the intersection is an ellipse.

      The generatrix of a cone is assumed to be infinite in length, extending in both directions from the vertex. The cone so generated, therefore, has two parts, called nappes or sheets, that extend infinitely. A finite cone has a finite, but not necessarily fixed, base, the surface enclosed by the directrix, and a finite, but not necessarily fixed, length of generatrix, called an element. See also conic section.

▪ plant anatomy
also called  strobilus 

      in botany, mass of scales or bracts, usually ovate in shape, containing the reproductive organs of certain nonflowering plants. The cone, a distinguishing feature of pines and other conifers, is also found on some club mosses and on horsetails.

▪ retinal cell
      light-sensitive cell (photoreceptor) with a conical projection in the retina of the vertebrate eye, associated with colour (colour vision) vision and perception of fine detail. Shorter and far fewer than the eye's rods (rod) (the other type of retinal light-sensitive cell), cones are less sensitive to low illumination levels and are mediators of photopic rather than scotopic (Greek skotos, “dark”) vision. Cones are mostly concentrated within the central retina (macula), which contains the fovea (depression in the retina), where no rods are present. In contrast, the outer edges of the retina contain few cones and many rods. Chemical changes that occur when light strikes the cones are ultimately relayed as impulses to optic-nerve fibres that enter the brain. See also colour vision.

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Universalium. 2010.

См. также в других словарях:

  • cône — cône …   Dictionnaire des rimes

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  • Cone — Cône Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom …   Wikipédia en Français

  • Cone — (k[=o]n?), n. [L. conus cone (in sense 1), Gr. kw^nos; akin to Skr. [,c]ana whetstone, L. cuneus wedge, and prob. to E. hone. See {Hone}, n.] 1. (Geom.) A solid of the form described by the revolution of a right angled triangle about one of the… …   The Collaborative International Dictionary of English

  • Coné — es un personaje de la tira cómica Condorito creada por Pepo. Apareció en la edición 22 de Condorito, en 1967. Es el sobrino de Condorito y vive como él en la ciudad ficticia de Pelotillehue. En una historieta revela que tiene 8 años recién… …   Wikipedia Español

  • cone — [ koun ] noun count * 1. ) an object with a circular base that rises to a point. Something in the shape of a cone is conical: a large building shaped like a cone a tower with a cone shaped roof 2. ) a cone shape that you put ice cream in and eat …   Usage of the words and phrases in modern English

  • CONE — CONE, U.S. commercial and philanthropic family. HERMAN CONE (1828–97), the father of 13 children, emigrated from Bavaria to the U.S. in 1845 and ultimately established a successful wholesale grocery business in Baltimore. His two eldest sons,… …   Encyclopedia of Judaism

  • Cone — ist der Name von: Personen: Fred P. Cone (1871–1948), amerikanischer Politiker Mac Cone (*1952), kanadischer Springreiter Schwestern Cone (1894–1929), Claribel und Eta Cone, amerikanische Gesellschaftsdamen und Kunstsammlerinnen Orten: Cone… …   Deutsch Wikipedia

  • cone — CONE. s. m. Terme de Mathématique. Pyramide ronde, corps solide, dont la base est un cercle, et qui se termine en pointe. Les pains de sucre sont faits en cône. f♛/b] On appelle Cône droit, Celui dont l axe est perpendiculaire à la base; et Cône… …   Dictionnaire de l'Académie Française 1798

  • cone — [kōn] n. [ME < L conus < Gr kōnos, a wedge, peak, cone < IE base kō(n) , to sharpen > HONE1, L cos] 1. a) a flat based, single pointed solid formed by a rotating straight line that traces out a closed curved base from a fixed vertex… …   English World dictionary

  • Cone — (k[=o]n), v. t. To render cone shaped; to bevfl like whe circwlar segoent of a cone; as, to cone the tires of car wheels. [1913 Webster] …   The Collaborative International Dictionary of English

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