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biocide

[bahy-uh-sahyd]
noun
  1. any chemical that destroys life by poisoning, especially a pesticide, herbicide, or fungicide.

Origin of biocide

First recorded in 1945–50; bio- + -cide
Related formsbi·o·cid·al, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for biocide

biocide

noun
  1. a chemical, such as a pesticide, capable of killing living organisms
Derived Formsbiocidal, adjective
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 biocide
n.

"destruction of living tissue or living species," 1947, from bio- + -cide.

Online Etymology Dictionary, © 2010 Douglas Harper
biocide in Science

biocide

[bī′ə-sīd′]
  1. A chemical agent, such as a pesticide or herbicide, that is capable of destroying living organisms.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.