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poisonous

[poi-zuh-nuh s]
See more synonyms for poisonous on Thesaurus.com
adjective
  1. full of or containing poison: poisonous air; a poisonous substance.
  2. harmful; destructive: poisonous to animals; poisonous rumors.
  3. deeply malicious; malevolent: poisonous efforts.
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Origin of poisonous

First recorded in 1565–75; poison + -ous
Related formspoi·son·ous·ly, adverbpoi·son·ous·ness, nounnon·poi·son·ous, adjectivenon·poi·son·ous·ly, adverbnon·poi·son·ous·ness, nounsem·i·poi·son·ous, adjectivesem·i·poi·son·ous·ly, adverbun·poi·son·ous, adjectiveun·poi·son·ous·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words

fatalnoxiousdangerousvirulentviciousperniciouslethaldeadlytoxicvenomousdestructivebadbalefulbanefulcorruptdeleteriousdetrimentalevilhurtfulmalicious

Examples from the Web for poisonous

Contemporary Examples

Historical Examples

  • If there is a poisonous one among them, the onion will turn black.

  • It is some of the rivers flowing into it that are poisonous.

    Aino Folk-Tales

    Basil Hall Chamberlain

  • Chemistry cannot tell us why some food is wholesome and other food is poisonous.

    Bunyan

    James Anthony Froude

  • From this I quote the following, which is by no means the most erring and most poisonous of their shafts.

    The Book of Khalid

    Ameen Rihani

  • "They're just weeds and some of them might be poisonous," he declared.

    L'Assommoir

    Emile Zola


British Dictionary definitions for poisonous

poisonous

adjective
  1. having the effects or qualities of a poison
  2. capable of killing or inflicting injury; venomous
  3. corruptive or malicious
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Derived Formspoisonously, adverbpoisonousness, noun
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 poisonous

adj.

1570s, from poison (n.) + -ous. Failed 16c. rivals were poisonsome, poisonful, poisony. Earlier poisoned was used (late 15c.). Related: Poisonously; poisonousness.

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Online Etymology Dictionary, © 2010 Douglas Harper

poisonous in Medicine

poisonous

(poizə-nəs)
adj.
  1. Relating to or caused by a poison.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.