[ hel-i-koid, hee-li- ]
/ ˈhɛl ɪˌkɔɪd, ˈhi lɪ- /


coiled or curving like a spiral.


Geometry. a warped surface generated by a straight line moving so as to cut or touch a fixed helix.

Origin of helicoid

First recorded in 1690–1700, helicoid is from the Greek word helikoeidḗs of spiral form. See helic-, -oid

Related forms

hel·i·coi·dal, adjectivehel·i·coi·dal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for helicoid


/ (ˈhɛlɪˌkɔɪd) /

adjective also: helicoidal

biology shaped like a spirala helicoid shell


geometry any surface resembling that of a screw thread

Derived Forms

helicoidally, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for helicoid


[ hĕlĭ-koid′, hēlĭ- ]


Arranged in or having the general shape of a flattened coil or spiral.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for helicoid


[ hĕlĭ-koid′, hēlĭ- ]


Arranged in or having the approximate shape of a flattened coil or spiral curve.


A surface in the form of a coil or screw. A helicoid is generated mathematically by rotating a plane or twisted curve about an axis at a fixed rate and simultaneously translating it in the direction of the line of axis, also at a fixed rate.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.