poisonous

adjective
poi·​son·​ous | \ ˈpȯiz-nəs How to pronounce poisonous (audio) , 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

Just before [Obama] left office, the Consumer Product Safety Commission had approved a proposal that would require generators to emit lower levels of the poisonous gas. Rachel Van Dongen, Washington Post, "The Daily 202: One Republican senator has the power to defeat Trump's Supreme Court nominee," 2 July 2018 If your pet ingests a poisonous substance, contact your local veterinarian right away or call the Animal Poison Control Center at 1-888-426-4435. Susannah Bryan, Sun-Sentinel.com, "Keep your pet safe on July 4th," 2 July 2018 The reported strain of E. coli, which produces poisonous substances known as Shiga toxins, can cause severe stomach cramps, bloody diarrhea and vomiting. Anchorage Daily News, "E. coli outbreak turns deadly with fatal case in California," 3 May 2018 Plants and Decorations: Beware when bringing festive plants into the home, many of these are poisonous to animals. Robin Tribble, Popular Mechanics, "How to Make Sure Your Pets Have a Happy Holiday Too," 12 Nov. 2018 Guests can learn to weave, hunt with a blowpipe, and fish sustainably with poisonous roots, but there are also opportunities to teach in the local school. Alex Postman, Condé Nast Traveler, "28 Places Our Travel Specialists Say You Should Go in 2019," 17 Dec. 2018 In one of the region’s most bizarre lynchings, townspeople in western Bolivia tied up a woman and her two sons to a tree infested with poisonous fire ants on New Year’s Eve in 2016, mistaking the trio for car thieves. Samantha Pearson, WSJ, "In Latin America, Awash in Crime, Citizens Impose Their Own Brutal Justice," 6 Dec. 2018 There’s lots of cover to hide behind, and, yes, a poisonous cloud steadily closes in, shrinking the battlefield. Andrew Webster, The Verge, "Supercell’s new game mixes Fortnite and Clash Royale, and it’s out soon," 14 Nov. 2018 Sadly, the only cure for a toxic culture is replacing poisonous executives, which is outside your scope of influence. Marie G. Mcintyre, The Seattle Times, "How bad is this workplace? Bosses covered the windows to keep workers from looking out," 14 Nov. 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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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 How to pronounce poisonous (audio) \

Kids Definition of poisonous

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

poisonous

adjective
poi·​son·​ous | \ ˈpȯiz-nəs, -ᵊn-əs How to pronounce poisonous (audio) \

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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