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poisonous

[poi-zuh-nuh s] /ˈpɔɪ zə nəs/
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.
Origin of poisonous
1565-1575
First recorded in 1565-75; poison + -ous
Related forms
poisonously, adverb
poisonousness, noun
nonpoisonous, adjective
nonpoisonously, adverb
nonpoisonousness, noun
semipoisonous, adjective
semipoisonously, adverb
unpoisonous, adjective
unpoisonously, adverb
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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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

/ˈpɔɪzənəs/
adjective
1.
having the effects or qualities of a poison
2.
capable of killing or inflicting injury; venomous
3.
corruptive or malicious
Derived Forms
poisonously, adverb
poisonousness, 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
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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.

Online Etymology Dictionary, © 2010 Douglas Harper
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poisonous in Medicine

poisonous poi·son·ous (poi'zə-nəs)
adj.
Relating to or caused by a poison.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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11
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