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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 ?
The parametric equations of a right-directional helicoid can be expressed as
Product's simple, yet rugged construction consists of one moving part: a helicoid screw that rotates inside a fixed tube.
m] - number of average Nusselt of a undulated wall; P - a helicoid step of the spiral, m; [U.
The Windstrument (TM) blade design is a conical helicoid pattern found extensively in nature - hurricanes, tornadoes, galaxies, animals and plants.
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.
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).
These spatial relationships can be illustrated by a plane cutting a helicoid.
The innocence of childhood lost, as in the previous quote, resonates with the reference of recently buried young, cadavers metaphorically described as "vasija de sexos adolescentes sin abrir" (189) or of a boy who was playing with his toy horse one moment and then after the detonation of a bomb's helicoid fuse, (2) becomes reduced to "pedazos de nino explotado" (208), the ultimate form of dismemberment that alludes to a borderline nothingness.
The cylindrical worm having the flanks as helical surfaces of a convolute helicoid of the second specie has the property that in the normal section on the reference medium helix of the tooth or of the tooth space.
calibrated VTA adjustment helicoid deep-thread technology similar to camera focus rings with lock
2000), Intelligent Manufacturing System for Production of Helicoid Surfaces, Gep, Vol.