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.
Despite its reputation for being poisonous, popular poinsettia (Euphorbia pulcherrima) has only mild effects if nibbled, the ASPCA says. Erica Browne Grivas, Better Homes & Gardens, 24 Nov. 2024 The plot is this: To stop a witness from testifying against him, a gangster stows away poisonous snakes in the cargo hold of a plane on which the witness is traveling. Mark Oppenheimer, The Hollywood Reporter, 25 Oct. 2024 Comfort can lull us into a sense of dull complacency, and fear comes in the form of a poisonous bouquet of toxicity that paralyzes us. Cherie Kloss, Forbes, 23 Oct. 2024 When cleaning mold spots, never mix bleach with ammonia or other cleaners, the agency warned, as this will produce a poisonous gas. Angelica Stabile, Fox News, 2 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 30 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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