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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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biology) biology shaped like a spiral: a helicoid shell.
(Mathematics) geometry any surface resembling that of a screw thread
ˌheliˈcoidally adv
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
"We were surprised by the SEBIN when refusing to leave our vehicle, they used a crane to move us forcibly to the Helicoid. The Democrats keep up the fight," was his last tweet before the car he was sitting in was towed away by the SEBIN officials.
The DNA-like spiraling structure, or helicoid, in the crystal sample that was the focus of the latest study exhibits a chirality or "handedness" -- as a person can be either left-handed or right-handed, and the left hand is a mirror image of the right hand.
The spiral organization of pili-shaped volumes produces a covered open-air atrium in the center of the building with a dramatic interior helicoid ramp terminating at the Mount Isarog viewing deck.
It is designed to produce a covered open-air atrium in the center of the building with a dramatic interior helicoid ramp terminating at the Mt.
The configuration of the helicoid and the central tube in a simple expansion chamber which is the subject of this investigation is a modified version of the Herschel-Quincke tube [7].
The wave equation for the scalar particle in the background of the Eguchi-Hanson metric [3] in four dimensions has hypergeometric functions as solutions [26], whereas the Nutku helicoid [27, 28] metric, the next higher one, gives us Mathieu functions [29], a member of the Heun function set, if the method of separation of variables is used to get a solution.
The ssDNA molecule is assumed to be a single helicoid, with a ruled surface having a helix as its boundary.
Two galleries dedicated to special exhibitions are connected by a graceful helicoid staircase.
The magnetic field inside the twisted tube is helicoid, [B.sub.i] = (0, [B.sub.i[phi]](r), [B.sub.iz](r)), while outside the tube the magnetic field is uniform and directed along the tube axis, [B.sub.e] = (0,0, [B.sub.e]).
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.