tox·​ic | \ ˈtäk-sik How to pronounce toxic (audio) \

Definition of toxic

 (Entry 1 of 3)

1 : containing or being poisonous material especially when capable of causing death or serious debilitation toxic waste a toxic radioactive gas an insecticide highly toxic to birds
2 : exhibiting symptoms of infection or toxicosis the patient became toxic two days later
3 : extremely harsh, malicious, or harmful toxic sarcasm
4 : relating to or being an asset that has lost so much value that it cannot be sold on the market



Definition of toxic (Entry 2 of 3)

: a toxic substance usually used in plural
variants: or toxico-

Definition of toxic- (Entry 3 of 3)

: poison toxicology

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Synonyms & Antonyms for toxic

Synonyms: Adjective

Synonyms: Noun

Antonyms: Adjective

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Frequently Asked Questions About toxic

What is the difference between toxic and poisonous?

The words toxic and poisonous are in many ways synonymous and interchangeable. Each word appears in at least one of the other’s definitions; one of the definitions of poisonous is "producing a toxic substance that causes injury or death when absorbed or ingested," and one of the definitions of toxic is "containing or being poisonous material especially when capable of causing death or serious debilitation." There are some ways in which they differ, such as when toxic refers to an actual toxin which is the product of a living organism while poisonous refers to a poison which may be artificially created.

What is the difference between toxic and noxious?

Toxic and noxious mean very similar things, but toxic has a connotation of severe harm or lethality more than noxious does. Both words have broadened figurative meanings as well.

What is a toxic person?

In addition to its original meaning concerning debilitating or lethal poisons, toxic has some figurative senses. Toxic can mean "extremely harsh, malicious, or harmful," which is often the intention when describing an individual as "toxic."

Examples of toxic in a Sentence

Adjective The fumes from that chemical are highly toxic. Tests will be run to determine if the landfill is toxic. Noun tested for toxics in the water supply
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Recent Examples on the Web: Adjective Leaders in workplaces may see mindfulness as a solution to the impacts of a toxic culture — a way to make everyone feel better. Forbes, 18 June 2021 Review of Northern California police squad ‘toxic culture’ is expanding. Laura Blasey, Los Angeles Times, 12 June 2021 Here’s a look at ricin, a natural, highly toxic compound that is extracted from castor beans. Cnn Editorial Research, CNN, 27 May 2021 Doctors in Salt Lake City told the Carriers their daughter had ingested something highly toxic. Anna Werner, CBS News, 11 May 2021 As an executive coach and consultant for decades, I have been retained to help teams and leaders navigate around poor leadership and to succeed inside a toxic culture. Dana Kaland, Forbes, 20 May 2021 Dell Loy Hansen decided to sell the franchise after allegations of racist behavior surfaced and he was tied to perpetuating a toxic workplace culture. Alex Vejar, The Salt Lake Tribune, 18 May 2021 The story of Blaine Wetzel, who’s a chef in his 30s, about the same age as you and me, also shows that this isn’t a simple story about how toxic restaurant culture is an old school versus new school thing, right? Soleil Ho, San Francisco Chronicle, 3 May 2021 Ten former Song Girls who spoke to The Times described a toxic culture within the famed collegiate dance program under Nelson’s leadership. Ryan Kartje, Los Angeles Times, 27 Apr. 2021 Recent Examples on the Web: Noun Their relationship has been fraught and low-key toxic from the beginning, but it's taken time and distance to see that clearly. Ineye Komonibo,, 15 June 2020 Because the whales feed near shore from the base of the food chain, even sucking up sediments and mud, their scat also could provide information about toxics in the environment, Giles said. Lynda Mapes, Anchorage Daily News, 28 Feb. 2020 Same with non-toxic, because the terms don't have concrete, universal definitions. Lindsay Schallon, Glamour, 17 Feb. 2020 More: Would Fab Five revival at Michigan turn Michigan State rivalry toxic? Chris Solari, Detroit Free Press, 3 Jan. 2020 Pollution, from oily toxics to plastics, spills into coastal waters. Craig Welch, National Geographic, 20 Sep. 2019 Adding certain types of biomass to the soil and covering it in plastic can kill the spores, as the material decomposes and releases gas toxic to bacteria and fungi. Erik Stokstad, Science | AAAS, 17 July 2019 From his initial charm to his subsequent gaslighting, Parker's behavior is textbook toxic. Elena Nicolaou,, 20 June 2019 Joseph has previously tested its drinking water for 2,4-D, the less toxic of the two chemicals. Rob Davis | The Oregonian/oregonlive,, 13 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'toxic.' 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 toxic


1664, in the meaning defined at sense 1


1890, in the meaning defined above

History and Etymology for toxic


Late Latin toxicus, from Latin toxicum poison, from Greek toxikon arrow poison, from neuter of toxikos of a bow, from toxon bow, arrow

Combining form

New Latin, from Latin toxicum

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Statistics for toxic

Last Updated

20 Jun 2021

Cite this Entry

“Toxic.” Dictionary, Merriam-Webster, Accessed 22 Jun. 2021.

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More Definitions for toxic



English Language Learners Definition of toxic

: containing poisonous substances


tox·​ic | \ ˈtäk-sik How to pronounce toxic (audio) \

Kids Definition of toxic

: containing, being, or caused by poisonous or dangerous material toxic waste toxic effects


tox·​ic | \ ˈtäk-sik How to pronounce toxic (audio) \

Medical Definition of toxic

 (Entry 1 of 2)

1 : containing or being poisonous material especially when capable of causing serious injury or death toxic drugs toxic gas
2 : of, relating to, or caused by a poison or toxin toxic liver damage
3a : affected by a poison or toxin
b : affected with toxemia of pregnancy toxic pregnant women



Medical Definition of toxic (Entry 2 of 2)

: a toxic substance

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tox·​ic | \ ˈtäk-sik How to pronounce toxic (audio) \

Legal Definition of toxic

1 : containing or being poisonous material especially when capable of causing death or serious debilitation
2 : having substantially lowered worth specifically : relating to or being an asset that has lost so much value that it cannot be sold on the market toxic assets toxic subprime loans

More from Merriam-Webster on toxic

Thesaurus: All synonyms and antonyms for toxic

Nglish: Translation of toxic for Spanish Speakers

Britannica English: Translation of toxic for Arabic Speakers


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