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

The National Park Service has said the debris tested positive for lead, chromium and other toxic metals. — ABC News, 18 Oct. 2026 Thankfully, the obsession over toxic masculinity remains a minority view. — Luka Ladan, New York Daily News, 18 Oct. 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

With the throne disengaged from governance, petitions and reports from officials piled up unread, crucial state posts went unfilled, and the imperial bureaucracy splintered amid poisonous factional infighting.

— Carl Minzner, Foreign Affairs, 5 Oct. 2026
With this potential even more poisonous investments in the bloated and indebted Paramount behemoth, there’s even more reason to reject it.

— Abigail Disney, New York Daily News, 28 Sep. 2026

Definition of poisonous

Noun

The first is to dramatically accelerate the pace of basic science, and the second is to accelerate curing disease and extending health span.

— Adam Kovac, Scientific American, 14 Oct. 2026
DeVeydt added that costs for inpatient services and pharmacy, particularly costly specialty pharmacy drugs for cancer and rare diseases, remain elevated.

— Annika Kim Constantino, CNBC, 13 Oct. 2026

Definition of disease

Noun

While raw materials potentially useful for Earth life are found in abundance on Mars, they are mixed in the soil with toxins such as perchlorate, as well as salts that would make growth difficult for most organisms.

— Charles Q. Choi, Space.com, 9 Oct. 2026
After the 2025 fires, there were complaints by residents that the FAIR Plan refused to test and remediate homes suffering damage by smoke, which can leave behind lead, asbestos and other toxins.

— Los Angeles Times, Los Angeles Times, 8 Oct. 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 20 Oct. 2026.

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Synonyms of toxic

adjective

noun

Example Sentences

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