-cide(word root) killExamples of words with the root -cide: homicideAbused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree-cidesuff.1. Killer: bactericide.2. Act of killing: ecocide.[Middle English, from Old French (from Latin -c?da, killer) and from Latin -c?dium, killing, both from caedere, to strike, kill; see ka?-id- in Indo-European roots.]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.-cide n combining form 1. indicating a person or thing that kills: insecticide. 2. (Law) indicating a killing; murder: homicide. [from Latin -c?da (agent), -c?dium (act), from caedere to kill] -cidal adj combining formCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014-cide a combining form meaning ?a person or thing that kills? or ?the act of killing? that specified by the initial element: homicide; pesticide. [late Middle English