poisonous

adjective
poi·​son·​ous | \ˈpȯiz-nəs, ˈpȯi-zᵊn-əs\

Definition of poisonous 

2a : having the properties or effects of poison poisonous gas

b : producing a toxic substance that causes injury or death when absorbed or ingested poisonous mushrooms also : venomous a poisonous spider

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Other Words from poisonous

poisonously adverb

Synonyms & Antonyms for poisonous

Synonyms

envenomed, poison, poisoned, toxic, venomous

Antonyms

nonpoisonous, nontoxic, nonvenomous

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Examples of poisonous in a Sentence

Chocolate is poisonous to dogs. This species of spider is extremely poisonous.

Recent Examples on the Web

Some wild plants are poisonous or can have serious adverse health effects. Janine Puhak, Fox News, "Instagram influencer’s cookbook recalled for potentially 'dangerous' recipes," 11 Aug. 2018 The seeds of the castor bean plant are naturally poisonous and can be used to create ricin. Kirsten Grieshaber And David Rising, chicagotribune.com, "German authorities thwart plot to use deadly toxin in attack, prosecutors say," 14 June 2018 The seeds of the castor bean plant are naturally poisonous and can be used to create ricin. Washington Post, "Prosecutor: Man makes deadly toxin for an attack in Germany," 14 June 2018 Also known as water moccasins, cottonmouths are one of six poisonous snakes found in the Tar Heel State, according to the North Carolina Wildlife Resources Commission. Kaitlyn Schallhorn, Fox News, "Venomous snakes found by North Carolina firefighter in floods after Florence," 18 Sep. 2018 Scary things happen: rogue coconuts, burning hair, poisonous snakes. New York Times, "Brief Tales for New Readers and Little Listeners From Philip Stead and More," 29 June 2018 The chaotic and bloody presidential politics of 1968 directly reflected the poisonous effects long-term of the Vietnam War on American society. Arthur I. Cyr, Lake County News-Sun, "Cyr: The essence of Memorial Day," 1 June 2018 It was formed in the aftermath of World War II where there was poisonous nationalism that caused two world wars in the twentieth century that killed more than 100 million people. Fox News, "Meadows, Dershowitz react after Lisa Page defies subpoena," 12 July 2018 The shell of the castor bean is highly poisonous and can be used to make ricin. Eric Schmitt, New York Times, "ISIS May Be Waning, but Global Threats of Terrorism Continue to Spread," 6 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'poisonous.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of poisonous

15th century, in the meaning defined at sense 2

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Statistics for poisonous

Last Updated

3 Dec 2018

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Time Traveler for poisonous

The first known use of poisonous was in the 15th century

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More Definitions for poisonous

poisonous

adjective

English Language Learners Definition of poisonous

: causing sickness or death by entering or touching the body : containing poison

: capable of putting poison into another animal's body by biting it

: very harmful or unpleasant

poisonous

adjective
poi·​son·​ous | \ˈpȯi-zᵊn-əs \

Kids Definition of poisonous

: containing poison : having or causing an effect of poison poisonous mushrooms

poisonous

adjective
poi·​son·​ous | \ˈpȯiz-nəs, -ᵊn-əs \

Medical Definition of poisonous 

1 : having the properties or effects of poison poisonous gas

2 : producing a toxic substance that causes injury or death when absorbed or ingested poisonous frogs and plants also : venomous

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Comments on poisonous

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