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

An accident at a plant owned by U.S. company Union Carbide (which later merged with Dow Chemicals in 2001) released at least 30 tons of a highly toxic gas, as well as a number of other poisonous gases. Nyay Bhushan, The Hollywood Reporter, "HBO's 'Chernobyl' Strikes a Chord in India, Leads to Calls for Bhopal Disaster Drama," 7 June 2019 The American Society for the Prevention of Cruelty to Animals has a searchable page for plants poisonous to dogs and cats and the ASPCA Animal Poison Control Center has a 24-hour emergency phone number: 888-426-4435. Robin Tribble, Popular Mechanics, "How to Make Sure Your Pets Have a Happy Holiday Too," 12 Nov. 2018 Make sure your office environment is safe and remove poisonous plants, hide cords and wires and secure toxic items. Kelly Tyko, USA TODAY, "Take your dog to work? These 'employees' wag their tails," 21 June 2018 Certainly poisonous plants, like certain types of lilies, daisies and azaleas, pose a much bigger threat than nontoxic plants, like roses, bamboo or baby’s breath. Michelle Higgins, sacbee, "Limit the impact that dogs, cats unleash on orderliness | The Sacramento Bee," 25 May 2018 Certainly poisonous plants, like certain types of lilies, daisies and azaleas, pose a much bigger threat than nontoxic plants, like roses, bamboo or baby’s breath. Michelle Higgins, New York Times, "Dogs and Cats and Decorating: It’s Easier Than You Think," 1 May 2018 It can only be used when discussing like household cleansers and poisonous plants. Fox News, "'Dragon energy': Kanye tweets his support of Trump," 26 Apr. 2018 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

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

18 Jun 2019

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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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Comments on poisonous

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