TOXIC Synonyms: 70 Similar and Opposite Words

toxic 1 of 2

adjective

ˈtäk-sik

Definition of toxic

as in poisonous

containing or contaminated with a substance capable of injuring or killing a living thing certain plants are toxic if eaten

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Antonyms & Near Antonyms

toxic

2 of 2

noun

as in poison

a substance that by chemical action can kill or injure a living thing tested for toxics in the water supply

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Example Sentences

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.

Recent Examples of toxic

Adjective

Or during 9/11, when so many lost their lives trying to save others, or died years later from exposure to toxic dust? — Voice Of The People, New York Daily News, 1 Nov. 2026 Eventually, the vessels burst, shooting the toxic blood out in jets. — Rj MacKenzie, Popular Science, 1 Nov. 2026

Noun

Manufacturers should be diligently working to clean up their supply chains and manufacturing practices to ensure their products are free of PFAS and other toxics. — Sarah Todd, STAT, 1 May 2026 The Michigan Legislature passed a law in 2008 meant to protect the public from harmful electronic waste toxics. — Nushrat Rahman, Freep.com, 27 Dec. 2025 See All Example Sentences for toxic

Recent Examples of Synonyms for toxic

Adjective

But major questions remained about how much space exists inside the Earth to store the CO2, how effectively it could be monitored and whether the poisonous, concentrated gas would reliably stay underground.

— Katie Worth, ProPublica, 30 Oct. 2026
Mirroring the poisonous arena featured in the movie, Grace paired her vibrant, beaded Almée Couture gown with a high ponytail, leaving her blond bangs out to frame her face.

— Arushi Jacob, Footwear News, 29 Oct. 2026

Definition of poisonous

Noun

The poison center data showed 233 deaths over the decade, most of which involved other substances like opioids, benzodiazepines, stimulants, and alcohol.

— Theresa Gaffney, STAT, 6 Nov. 2026
When this disintegration occurs, toxic components of the muscle fibers can enter the circulatory system and kidneys, which can cause kidney damage, essentially acting as poison to the body.

— Angelica Stabile, FOXNews.com, 3 Nov. 2026

Definition of poison

Noun

Plus, most rooms have a recycling bin in addition to a trash bin in the larger kitchenettes and the custom mattresses are eco-friendly, US made, and toxin-free.

— Condé Nast, Condé Nast Traveler, 4 Nov. 2026
Botox 101 Botulinum toxin injections, like Botox, are the most common minimally invasive cosmetic procedure performed in the United States, accounting for about half of the total.

— Norah O'Donnell, CBS News, 4 Nov. 2026

Definition of toxin

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tows

toxic

toxicant

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“Toxic.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/toxic. Accessed 8 Nov. 2026.

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Synonyms of toxic

adjective

noun

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