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definitions

cyclo-

  1. a combining form meaning “cycle,” used in the formation of compound words: cyclohexane.
Also especially before a vowel, cycl-.

Origin of cyclo-

< Greek kyklo-, combining form of kýklos circle, ring; cognate with Sanskrit cakra, wheel
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for cyclo-

cyclo-

before a vowel cycl-

combining form
  1. indicating a circle or ringcyclotron
  2. denoting a cyclic compoundcyclohexane

Word Origin for cyclo-

from Greek kuklos cycle
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
Word Origin and History for cyclo-

before a vowel, cycl-, word-forming element meaning "circle, ring, rotation," from Latinized form of Greek kyklo-, comb. form of kyklos "circle, wheel, ring" (see cycle (n.)).

Online Etymology Dictionary, © 2010 Douglas Harper
cyclo- in Medicine

cyclo-

pref.
  1. Circle; cycle:cyclophoria.
  2. A cyclic compound:cyclopeptide.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.