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definitions

electro-

  1. a combining form representing electric or electricity in compound words: electromagnetic.
Also especially before a vowel, electr-.

Origin of electro-

electr(ic) + -o-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for electro-

electro-

sometimes before a vowel electr-

combining form
  1. electric or electricallyelectrocardiograph; electrocute
  2. electrolyticelectroanalysis

Word Origin for electro-

from New Latin, from Latin ēlectrum amber, from Greek ēlektron
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 electro-

before vowels electr-, word-forming element meaning "electrical, electricity," Latinized form of Greek elektro-, comb. form of elektron "amber" (see electric).

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

electro-

pref.
  1. Electricity; electric; electrically:electrocautery.
  2. Electron:electronegative.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.