• Screwdriver.  Screwdriver-Bit.  Spiral Screwdriver
    Screwdriver. Screwdriver-Bit. Spiral Screwdriver
  • WordNet 3.6
    • adj spiral in the shape of a coil
    • v spiral to wind or move in a spiral course "the muscles and nerves of his fine drawn body were coiling for action","black smoke coiling up into the sky","the young people gyrated on the dance floor"
    • v spiral move in a spiral or zigzag course
    • v spiral form a spiral "The path spirals up the mountain"
    • n spiral flying downward in a helical path with a large radius
    • n spiral a structure consisting of something wound in a continuous series of loops "a coil of rope"
    • n spiral ornament consisting of a curve on a plane that winds around a center with an increasing distance from the center
    • n spiral a continuously accelerating change in the economy
    • n spiral a plane curve traced by a point circling about the center but at increasing distances from the center
    • n spiral a curve that lies on the surface of a cylinder or cone and cuts the element at a constant angle
    • ***

Additional illustrations & photos:

A repeated and complex spiral, wheel and lotus design A repeated and complex spiral, wheel and lotus design

Webster's Revised Unabridged Dictionary
  • Interesting fact: Spiral staircases in medieval castles are running clockwise. This is because all knights used to be right-handed. When the intruding army would climb the stairs they would not be able to use their right hand which was holding the sword because of the difficulties of climbing the stairs. Left-handed knights would have had no troubles, except left-handed people could never become knights because it was assumed that they were descendants of the devil
    • Spiral (Geom) A plane curve, not reëntrant, 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.
    • Spiral Anything which has a spiral form, as a spiral shell.
    • Spiral (Geom) Of or pertaining to a spiral; like a spiral.
    • Spiral Winding or circling round a center or pole and gradually receding from it; as, the spiral curve of a watch spring.
    • Spiral Winding round a cylinder or imaginary axis, and at the same time rising or advancing forward; winding like the thread of a screw; helical.
    • ***
Century Dictionary and Cyclopedia
  • Interesting fact: The reason why some people get a cowlick is because the growth of their hair is in a spiral pattern, which causes the hair to either stand straight up, or goes to a certain angle
    • spiral Of or pertaining to a spire or coil; like a spire; pointed or shaped like a spire.
    • spiral Winding around a fixed point or center, and continually receding from it, like a watchspring; specifically, in conchology, making a number of turns about the columella or axis of the shell; whorled. The whorls may be in one plane, producing the flat or discoid shell, or oftener wound into a spire, resulting in the ordinary turreted form. Compare cuts under Planorbis and Limnæa, and see spire, 2.
    • spiral Winding and at the same time rising or advancing like a screw-thread: more accurately helical or helicoidal.
    • n spiral In geometry, a plane curve which runs continuously round and round a fixed point, called the center, with constantly increasing radius vector, so that the latter is never normal to the curve; also, a part of such a curve in the course of which the radius from the center describes 360°. Besides the spirals mentioned below, the involute of the circle and the cyclodes are very important. The principal spirals which have received attention are the spiral of Archimedes (usually understood to have been discovered by Conon the Samian), the radius of which increases uniformly with the angle; the hyperbolic spiral, whose radius vector is inversely proportional to the angle; the lituus, the square of whose radius vector is inversely proportional to the angle; and the logarithmic spiral, whose angle is proportional to the logarithm of the radius vector.
    • n spiral A helix or curve which winds round a cylinder like a screw.
    • n spiral A spiral spring.
    • n spiral In wool, one of the curls or convolutions in wool-fiber, the number of which in a unit of length is made the basis of an estimate of its quality for manufacturing.
    • n spiral In zoology and anatomy, a spiral formation, as of a univalve, of the cochlea, etc.
    • spiral To make spiral; cause to move spirally.
    • n spiral A loop in a railroad line used to overcome steep grades in a mountainous region by carrying the line through a continuously rising curve. Spirals may be cut entirely within a mountain in the form of a constantly turning and rising tunnel, the outlet being much higher than the inlet. The more common valley spirals consist of double loops or complicated curves which return and pass under or over one another, by means of tunnels or bridges, on a continuously risiug grade. The spiral loop on the Georgetown branch of the Union Pacific Railroad is an example of a valley spiral.
    • n spiral of a point: The origin of coördinates O corresponds to v = o, and the asymptotic points, P′ , P1, round which the curve goes in an ever-closing spiral, correspond to v = ±∞. The intrinsic equation, expressing the relation between the arc σ (measured from O)and the inclination φ of the tangent at any point to the axis of x, is φ = ½πσ.
    • spiral To assume a spiral form; move in a spiral course.
    • ***
Chambers's Twentieth Century Dictionary
  • Interesting fact: Barbers at one time combined shaving and haircutting with bloodletting and pulling teeth. The white stripes on a field of red that spiral down a barber pole represent the bandages used in the bloodletting.
    • adj Spiral spī′ral pertaining to, or like, a spire: winding like the thread of a screw
    • n Spiral a spiral line: a curve which continually recedes from a centre about which it revolves: a screw
    • ***


  • Johann Wolfgang Von Goethe
    “Progress has not followed a straight ascending line, but a spiral with rhythms of progress and retrogression, of evolution and dissolution.”


Webster's Revised Unabridged Dictionary
Cf. F. spiral,. See Spire a winding line


In literature:

In my book, "Hypnotism Revealed," a picture of the hypnodisc unit with the hypnodisc spiral attached is shown.
"A Practical Guide to Self-Hypnosis" by Melvin Powers
Spiral spring, to draw, 166.
"Mechanical Drawing Self-Taught" by Joshua Rose
Spirally-twisted stem of teazel 321 173.
"Vegetable Teratology" by Maxwell T. Masters
This figure has the form of two concentric spirals, the ends of which do not join.
"Archeological Expedition to Arizona in 1895" by Jesse Walter Fewkes
I went on down in a steep spiral, guiding myself by them, and seeing nothing.
"High Adventure" by James Norman Hall
Spiral or Whirlpool Nebulae.
"Aether and Gravitation" by William George Hooper
Each smoke was ascending in spiral rings, and he knew that they were talking together.
"The Eyes of the Woods" by Joseph A. Altsheler
A' spiraled up and A' nose-dived doon, and she stayed wi' me closer than a sister.
"Tam O' The Scoots" by Edgar Wallace
Then a thirteenth object winked into being, began the encircling, closing spiral of descent.
"The Defiant Agents" by Andre Alice Norton
These are two feet in length, and marked by a ridge that passes spirally around them nearly to the tips.
"Popular Adventure Tales" by Mayne Reid

In poetry:

In the wilds of Space, in the dark,
Spiral nebulae
Twirl spark upon spark,
Whereof one are we.
"Night " by Lord Dunsany Edward Plunkett
Sun Eyes!
Glowing and glad; a flame of pure delight,
Fanning the spirals of Love's fire to rise
Within me, and attain your holy height.
"The Eyes Of Fionuala" by Anna Johnston MacManus
"Thou com'st with me, thou butcher man!"--
He strives to loose his grasp,
But, faster than the clinging vine,
Those twining spirals clasp;
"The Spectre Pig" by Oliver Wendell Holmes
With spiral shell, Full-blasted, tell,
That all your watery realms should ring;
Your pearl alcoves, Your coral groves,
Should echo theirs and Britain's king.
"Ocean: An Ode. Concluding With A Wish." by Edward Young
And if we should meet the Snow,
Whirling in spirals,
And he should blind my eyes…
Ally, you will defend me - You will hold me close,
Blowing on my eyelids.
"North Wind" by Lola Ridge
TO-NIGHT the air discloses
Souls of a million roses,
And ghosts of hyacinths that died too soon;
From Pan's safe-hidden altar
Dim wraiths of incense falter
In waving spiral, making sweet the moon!
"In An Autumn Garden" by Isabel Ecclestone Mackay

In news:

Oldest spiral galaxy in universe discovered.
(Space.com) Astronomers have discovered the universe's most ancient spiral galaxy yet, a cosmic structure that dates back roughly 10.7 billion years, a new study reveals.
The discovery with Hubble Space Telescope of a spiral galaxy , long before other galaxies are known to have formed, surprised scientists.
Using Hubble, astronomers spot oldest spiral galaxy ever seen.
Hubble spots spiral galaxy that shouldn't exist.
Hubble Captures Nearby Spiral Galaxy .
Athens has spiraling HIV crisis.
New law aims to stem spiraling cost of health care.
Spiraling state of welfare spending.
N.J.'s local tax bills keep spiraling upward.
Grand Valley State's football season spiraling after loss to 1-5 team.
Buckeye fans wear their hearts on their sleeves again as jersey sales are spiraling .
'Little Birds': Spiraling Down On Broken Wings.
Nets' season spiraling downhill already.
Calderón administration slams Mexico's state governments for spiraling debt.

In science:

The property of the Cornu spiral is that (dt)2 is proportional to (dℓ)2 where dℓ is the distance between the points corresponding to t and t + dt.
Paraxial propagation of a quantum charge in a random magnetic field
For the point with the coordinates x, y , the wave function ψ(x, y ) corresponds to the point on the Cornu spiral with the arc-length equal to ˜y = y/√2λx .
Paraxial propagation of a quantum charge in a random magnetic field
Spiral density wave theory states that a four arm spiral cannot exist for Ωp > Ω + κ/4.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
Their fractional rate in Spiral galaxies, depends on the spiral type and to a larger extent, the analysis used to derive the numbers.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
Their runs also illustrate that tilting alone does not give rise to spiral arms, as is expected from the opposite vertical parities of the tilted halo perturbed potential and the spiral density wave, showing that triaxiality (with figure rotation) is essential.
On the Spiral Structure of NGC 2915 and Dark Matter