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-cide

a learned borrowing from Latin meaning “killer,” “act of killing,” used in the formation of compound words: pesticide, homicide.

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Origin of -cide

late Middle English < Latin -cīda killer, -cīdium act of killing, derivatives of caedere to cut down, kill (in compounds -cīdere)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for -cide

-cide

n combining form

indicating a person or thing that killsinsecticide
indicating a killing; murderhomicide
Derived Forms-cidal, adj combining form

Word Origin for -cide

from Latin -cīda (agent), -cīdium (act), from caedere to kill
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 -cide

word-forming element meaning "killer," from French -cide, from Latin -cida "cutter, killer, slayer," from -cidere, comb. form of caedere "to strike down, chop, beat, hew, fell, slay," from PIE *kae-id-, from root *(s)k(h)ai- "to strike" (Pokorny, not in Watkins; cf. Sanskrit skhidati "beats, tears," Lithuanian kaisti "shave," German heien "beat"). For Latin vowel change, see acquisition. The element also can represent "killing," from French -cide, from Latin -cidium "a cutting, a killing."

Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for -cide

-cide

suff.

Killer:bactericide.
Act of killing:suicide.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science definitions for -cide

-cide

A suffix that means “a killer of.” It is used to form the names of chemicals that kill a specified organism, such as pesticide, a chemical that kills pests.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.