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poisonous

[ poi-zuh-nuhs ]
/ ˈpɔɪ zə nəs /
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See synonyms for: poisonous / poisonousness on Thesaurus.com

adjective
full of or containing poison: poisonous air; a poisonous substance.
harmful; destructive: poisonous to animals; poisonous rumors.
deeply malicious; malevolent: poisonous efforts.

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Origin of poisonous

First recorded in 1565–75; poison + -ous

OTHER WORDS FROM poisonous

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use poisonous in a sentence

British Dictionary definitions for poisonous

poisonous
/ (ˈpɔɪzənəs) /

adjective
having the effects or qualities of a poison
capable of killing or inflicting injury; venomous
corruptive or malicious

Derived forms of poisonous

poisonously, 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

Medical definitions for poisonous

poisonous
[ poizə-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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