spi⋅ral
[spahy-ruh
l]
noun, adjective, verb, -raled, -ral⋅ing or (especially British
) -ralled, -ral⋅ling.| 1. | Geometry. a plane curve generated by a point moving around a fixed point while constantly receding from or approaching it. |
| 2. | a helix. |
| 3. | a single circle or ring of a spiral or helical curve or object. |
| 4. | a spiral or helical object, formation, or form. |
| 5. | Aeronautics. a maneuver in which an airplane descends in a helix of small pitch and large radius, with the angle of attack within that of the normal flight range. |
| 6. | Football. a type of kick or pass in which the ball turns on its longer axis as it flies through the air. |
| 7. | Economics. a continuous increase in costs, wages, prices, etc. (inflationary spiral), or a decrease in costs, wages, prices, etc. (deflationary spiral). |
| 8. | running continuously around a fixed point or center while constantly receding from or approaching it; coiling in a single plane: a spiral curve. |
| 9. | coiling around a fixed line or axis in a constantly changing series of planes; helical. |
| 10. | of or of the nature of a spire or coil. |
| 11. | bound with a spiral binding; spiral-bound: a spiral notebook. |
| 12. | to take a spiral form or course. |
| 13. | to advance or increase steadily; rise: Costs have been spiraling all year. |
| 14. | Aeronautics. to fly an airplane through a spiral course. |
| 15. | to cause to take a spiral form or course. |
Based on the Random House Dictionary, © Random House, Inc. 2009.
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Copyright © 2009 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Spiral
Spi"ral\, a. [Cf. F. spiral. See Spire a winding line.]1. Winding or circling round a center or pole and gradually receding from it; as, the spiral curve of a watch spring. 2. Winding round a cylinder or imaginary axis, and at the same time rising or advancing forward; winding like the thread of a screw; helical. 3. (Geom.) Of or pertaining to a spiral; like a spiral. Spiral gear, or Spiral wheel (Mach.), a gear resembling in general a spur gear, but having its teeth cut at an angle with its axis, or so that they form small portions of screws or spirals. Spiral gearing, a kind of gearing sometimes used in light machinery, in which spiral gears, instead of bevel gears, are used to transmit motion between shafts that are not parallel. Spiral operculum, an operculum whih has spiral lines of growth. Spiral shell, any shell in which the whorls form a spiral or helix. Spiral spring. See the Note under Spring, n., 4.Spiral
Spi"ral\, n. [Cf. F. spirale. See Spiral, a.]1. (Geom.) A plane curve, not re["e]ntrant, described by a point, called the generatrix, moving along a straight line according to a mathematical law, while the line is revolving about a fixed point called the pole. Cf. Helix. 2. Anything which has a spiral form, as a spiral shell. Equiangular spiral,a plane curve which cuts all its generatrices at the same angle. Same as Logarithmic spiral, under Logarithmic. Spiral of Archimedes, a spiral the law of which is that the generatrix moves uniformly along the revolving line, which also moves uniformly.Cite This Source
spiral (adj.)
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Main Entry: 1spi·ral
Pronunciation: 'spI-r&l
Function: adjective
1 a : winding around a center or pole and gradually recedingfrom or approaching it b : HELICAL
2 : being afracture in which the break is produced by twisting apart the bone spiral break> —spi·ral·ly /-r&-lE/ adverb
Main Entry: 2spiral
Function: noun
1 : the path of a point in a plane moving around a central point while continuously receding from or approaching it
2 : a three-dimensional curve (as a helix) with one or more turns about an axis
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spiral spi·ral (spī'rəl)
adj.
Coiling or developing around an axis in a constantly changing series of planes; helical. n.
A structure in the shape of a coil. v. spi·raled or spi·ralled, spi·ral·ing or spi·ral·ling, spi·rals or spi·rals
To take the form or course of a spiral.
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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spiral
plane curve that, in general, winds around a point while moving ever farther from the point. Many kinds of spiral are known, the first dating from the days of ancient Greece. The curves are observed in nature, and human beings have used them in machines and in ornament, notably architectural-for example, the whorl in an Ionic capital. The two most famous spirals are described below.
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