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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Antonyms & Near Antonyms

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 team created a lightweight, non-toxic porous material by mechanically grinding the entire composite, both fiber and resin. — Mrigakshi Dixit, Interesting Engineering, 19 Aug. 2026 These are toxic to the environment and water and should never be thrown in the regular trash cans for disposal! — Ticked Off, The Orlando Sentinel, 19 Aug. 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

For this reason, these poisonous mushrooms are more commonly confused with other types of edible mushrooms like chicken of the woods and chanterelles (more on these in a minute).

— Katie Hill, Outdoor Life, 6 Aug. 2026
Perhaps ducks had been used as bio-processors, feeding on toads and metabolizing their poisonous compounds so that humans could safely consume them.

— Kimon de Greef, Longreads, 4 Aug. 2026

Definition of poisonous

Noun

Rather than being a delightful add-on, rechargeability in a poison-snooper could save lives in non-electrified remote locations, or in disaster zones where electricity is temporarily unavailable.

— New Atlas, New Atlas, 17 Aug. 2026
Wildlife officials had found that many of these poisons worked their way through the food chain, sickening and killing owls, raptors, coyotes and mountain lions.

— Lila Seidman, Los Angeles Times, 16 Aug. 2026

Definition of poison

Noun

Those enrolled have experienced CLBP due to degenerative disc disease (DDD) for less than five years.

— New Atlas, New Atlas, 19 Aug. 2026
Prices of the precious commodity have swung dramatically from one season to the next, particularly as issues such as climate change, water scarcity and pest and disease pressures persist.

— Sam Meredith, CNBC, 19 Aug. 2026

Definition of disease

Noun

The nectar might contain some toxins, but the hummers and moths don’t drink enough to be harmed.

— Joan Morris, Mercury News, 17 Aug. 2026
These include tenocytes [the primary component of tendons]; the cells that wrap around blood vessels and stabilize the circulatory system; the smooth muscle cells of the colon; and kidney epithelial cells, which filter toxins from the blood.

— Ingrid Wickelgren, Quanta Magazine, 14 Aug. 2026

Definition of toxin

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tows

toxic

toxicant

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Style

“Toxic.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/toxic. Accessed 22 Aug. 2026.

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Synonyms of toxic

adjective

noun

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