poisonous
Americanadjective
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full of or containing poison.
poisonous air; a poisonous substance.
-
harmful; destructive.
poisonous to animals; poisonous rumors.
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deeply malicious; malevolent.
poisonous efforts.
adjective
-
having the effects or qualities of a poison
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capable of killing or inflicting injury; venomous
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corruptive or malicious
Other Word Forms
- nonpoisonous adjective
- nonpoisonously adverb
- nonpoisonousness noun
- poisonously adverb
- poisonousness noun
- semipoisonous adjective
- semipoisonously adverb
- unpoisonous adjective
- unpoisonously adverb
Etymology
Origin of poisonous
Compare meaning
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
It’s got poisonous lead in it from paint.
From Salon • Mar. 6, 2026
Hydrogen cyanide, which is highly poisonous, can freeze into crystals at low temperatures.
From Science Daily • Jan. 16, 2026
There’s no silver bullet for finding out whether a wild mushroom is poisonous unless you know what species it is, said Rudy Diaz, president of the Los Angeles Mycological Society.
From Los Angeles Times • Dec. 10, 2025
Perhaps, but it also gave an immediacy bordering on desperation to a story of teenage identity, poisonous social media and murder.
From The Wall Street Journal • Nov. 24, 2025
Who knew better how poisonous the soil was in Weep than she who had been poisoning it for ten long years?
From "Strange the Dreamer" by Laini Taylor
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
