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Related to helicoid: Catenoid, helicoid cyme
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a helicoid generated by rotating and translating a line at a constant rate about an axis to which it is perpendicular


 (hĕl′ĭ-koid′, hē′lĭ-)
Arranged in or having the approximate shape of a flattened coil or spiral.
n. Mathematics
A surface in the form of a coil or screw.

[Greek helikoeidēs : helix, helik-, spiral; see helix + -oeidēs, -oid.]


(Biology) biology shaped like a spiral: a helicoid shell.
(Mathematics) geometry any surface resembling that of a screw thread
ˌheliˈcoidally adv


(ˈhɛl ɪˌkɔɪd, ˈhi lɪ-)

1. coiled or curving like a spiral.
2. a warped geometric surface generated by a straight line moving so as to cut or touch a fixed helix.
[1690–1700; < Greek helikoeidḗs. See helix, -oid]
hel`i•coi′dal, adj.
References in periodicals archive ?
Two galleries dedicated to special exhibitions are connected by a graceful helicoid staircase.
The Speedfight's styling is inspired by the Peugeot Exalt concept car, with twin helicoid headlights, separated by the distinctive grille and aviation-style fuel cap.
This is a unique version of the ZI helicoid involute tooth form.
It uses the helicoid focussing mechanism, and has a 37 degrees field of view It brings in the dreamy world of soft focus on photographs if you shoot at apertures below f/4, and also has support for Lumiere and Aquarelle aperture plates that add soft radiance glow and textures to photographs, respectively.
The parametric equations of a right-directional helicoid can be expressed as
Thus, the circular type shows a wide variety, from simple models without internal divisions, to more complex and internally structured models with several formats that range from a simple dividing axis to much more elaborated helicoid, draught-board or cruciform compositions.
m] - number of average Nusselt of a undulated wall; P - a helicoid step of the spiral, m; [U.
Product's simple, yet rugged construction consists of one moving part: a helicoid screw that rotates inside a fixed tube.
A study led by researchers from McGill University reveals that the muscle fibers in the heart wall are locally arranged in a special "minimal surface," the generalized helicoid.
A diopter ring with click stops holds adjustments, while Helicoid eyepieces with click stops make them compatible for those with or without eyeglasses.
Three projects are thus drawn up with normal way, including two with rack and pinion, and another requiring the boring of a 1100 m helicoid tunnel, it is the third layout which is retained, but the tunnel proving of a prohibitory cost, it is replaced by a graining in the open air, source of notable operational difficulties, all the more regrettable as the layout of this line often passes to 3-4 km from the center of the villages which it serves.
However, subsequent studies have shown that the East African species referred by Thiele (1911) to Rhytida Martens, 1860 are in fact helicoid streptaxids belonging to the genus Tayloria Bourguignat, 1889 (Pilsbry 1919; Verdcourt 1958).