Geometry. a plane curve generated by a point moving around a fixed point while constantly receding from or approaching it.
a single circle or ring of a spiral or helical curve or object.
a spiral or helical object, formation, or form.
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.
Football. a type of kick or pass in which the ball turns on its longer axis as it flies through the air.
Economics. a continuous increase in costs, wages, prices, etc. (inflationary spiral) or a decrease in costs, wages, prices, etc. (deflationary spiral)
running continuously around a fixed point or center while constantly receding from or approaching it; coiling in a single plane:
a spiral curve.
coiling around a fixed line or axis in a constantly changing series of planes; helical.
of or of the nature of a spire or coil.
bound with a spiral binding; spiral-bound:
a spiral notebook.
verb (used without object), spiraled, spiraling or (especially British) spiralled, spiralling.
to take a spiral form or course.
to advance or increase steadily; rise:
Costs have been spiraling all year.
Aeronautics. to fly an airplane through a spiral course.
verb (used with object), spiraled, spiraling or (especially British) spiralled, spiralling.
to cause to take a spiral form or course.
(geometry) one of several plane curves formed by a point winding about a fixed point at an ever-increasing distance from it. Polar equation of Archimedes spiral:r = aθ; of logarithmic spiral: log r = aθ; of hyperbolic spiral:rθ = a, (where a is a constant)
another name for helix (sense 1)
something that pursues a winding, usually upward, course or that displays a twisting form or shape
a flight manoeuvre in which an aircraft descends describing a helix of comparatively large radius with the angle of attack within the normal flight range Compare spin (sense 16)
(economics) a continuous upward or downward movement in economic activity or prices, caused by interaction between prices, wages, demand, and production
having the shape of a spiral
verb -rals, -ralling, -ralled (US) -rals, -raling, -raled
to assume or cause to assume a spiral course or shape
(intransitive) to increase or decrease with steady acceleration: wages and prices continue to spiral
spiral spi·ral (spī’rəl)
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.
- Spiral model
programming A software life-cycle model which supposes incremental development, using the waterfall model for each step, with the aim of managing risk. In the spiral model, developers define and implement features in order of decreasing priority. [Barry Boehm, “A Spiral Model of Software Development and Enhancement”, ACM SIGSOFT Software Engineering Notes, August 1986]. [Barry Boehm […]
noun, Astronomy. 1. (formerly) a spiral galaxy.
noun, Geometry. 1. a curve that is the locus of a point that moves outward with uniform speed along a vector, beginning at the origin, while the vector rotates about the origin with uniform angular velocity. Equation (in polar coordinates): r = aθ. spiral of Archimedes noun 1. (maths) a spiral having the equation r […]
- Spiral organ
spiral organ n. A specialized structure located on the inner surface of the basilar membrane of the cochlea containing hair cells that transmit sound vibrations to the nerve fibers. Also called organ of Corti.