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.
Seven-percent mortgages have been poisonous to homebuilders, and Horton was down 26% in the fourth quarter – in a rising market, at that. John Dorfman, Forbes, 20 Jan. 2025 Social platforms are poised to become even more poisonous to their own users as a handful of outrageously rich and powerful men grapple with their own insecurities around masculinity and free speech. Megan Farokhmanesh, WIRED, 15 Jan. 2025 Mushrooms sold from a truck in a Salinas parking lot turned out to be poisonous, sending three people to the hospital, California health officials warned. Don Sweeney, Sacramento Bee, 6 Jan. 2025 And there were giant spiders that were poisonous and stuff on the edge of the trees. Nick Romano, EW.com, 18 Dec. 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 24 Jan. 2025.

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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