poisonous

adjective

poi·​son·​ous ˈpȯiz-nəs How to pronounce poisonous (audio)
ˈpȯi-zᵊn-əs
1
2
a
: 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
3
poisonously adverb

Examples of poisonous in a Sentence

Chocolate is poisonous to dogs. This species of spider is extremely poisonous.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This genus is primarily known for its small but brightly colored amphibian species that are highly poisonous, most notably, the bright orange pumpkin toadlets, B. rotenbergae, B. ephippium and B. pitanga (more here). Grrlscientist, Forbes, 1 Nov. 2024 Its most frightening aspect, though, is probably its poisonous bite. Paul Smaglik, Discover Magazine, 22 Oct. 2024 But social media and polarized politics are exposing it at industrial scale, fueled by a poisonous cocktail of bad actors, media illiteracy and plummeting trust in traditional news. Zachary Basu, Axios, 19 Oct. 2024 Craddock writes this because it was variously believed that the spirit was medicinal (nope), poisonous (not especially) or hallucinogenic (not even close). Jason O'Bryan, Robb Report, 12 Oct. 2024 See all Example Sentences for poisonous 

Word History

First Known Use

15th century, in the meaning defined at sense 2

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

Dictionary Entries Near poisonous

Cite this Entry

“Poisonous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/poisonous. Accessed 22 Nov. 2024.

Kids Definition

poisonous

adjective
poi·​son·​ous ˈpȯiz-nəs How to pronounce poisonous (audio)
-ᵊn-əs
: containing poison : having or causing an effect of poison
poisonously adverb

Medical Definition

poisonous

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

More from Merriam-Webster on poisonous

Last Updated: - Updated example sentences
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