tox·​ic·​i·​ty täk-ˈsi-sə-tē How to pronounce toxicity (audio)
plural toxicities
: the quality or state of being toxic: such as
: the quality, state, or relative degree of being poisonous
measuring the toxicity level of the soil
The toxicity of some chemical agents degrades significantly over time, so it is unclear how lethal the stockpiles are.David S. Cloud
Administering a cocktail of drugs would dilute the toxicities of the different drugs and minimize the development of viral resistance to them.Rudy M. Baum and Ron Dagani
: an extremely harsh, malicious, or harmful quality
In the past few days, I've tuned in to C-SPAN to watch a number of the televised Senate debates, which illustrate all too vividly the toxicity of an uncivil tongue.Connie Schultz
In much of the ensuing commentary, court watchers worried that the justices' soaring rates of written dissents, nasty and personal attacks and scathing remarks read aloud from the bench bespeak a new toxicity in Supreme Court discourse.Dahlia Lithwick

Did you know?

Toxicity is often a relative thing; in the words of a famous old saying, "The dose makes the poison". Thus, it's possible to die from drinking too much water, and lives have been saved by tiny doses of arsenic. Even though botulinum toxin is the most toxic substance known, it's the basic ingredient in Botox, which is injected into the face to get rid of wrinkles. With some poisons, mere skin contact can be lethal; others are lethal when breathed into the lungs in microscopic amounts. To determine if a chemical will be officially called a poison, researchers often use the "LD50" test: If 50 milligrams of the substance for every kilogram of an animal's body weight results in the death of 50% of test animals, the chemical is a poison. But there are problems with such tests, and toxicity remains a very individual concept.

Examples of toxicity in a Sentence

Recent Examples on the Web Experts tell Fortune that what might begin as a productivity aid could turn into a not-so-subtle power move that breeds toxicity. Lila MacLellan, Fortune, 10 Nov. 2023 By Cady Lang October 19, 2023 4:51 PM EDT There may be no relationship that epitomized both the allure and the toxicity of early-aughts celebrity culture as much as the three-year relationship of Britney Spears and Justin Timberlake. TIME, 19 Oct. 2023 However, these symptoms and others reported in similar incidents aren't usually associated with opioid toxicity. Kerry Breen, CBS News, 21 Sep. 2023 The typical American needn’t change a thing to prevent water toxicity, Fairbrother reassures. Erin Prater, Fortune Well, 2 Nov. 2023 The playwright posits Juicy as a Hamlet-adjacent symbol of Gen Z ambivalence — a young person adrift in the culture, with only vague job plans and a reluctance to deal with his family’s toxicity. Peter Marks, Washington Post, 1 Nov. 2023 Additionally, taking the pills has general risks, like caffeine toxicity, and can be riskier for some individuals than others. Jenna Wirth, Health, 30 Oct. 2023 Environmental Protection Agency The EPA also claims eBay unlawfully sold at least 23,000 pesticide products, including a high toxicity insecticide banned in the U.S., and over 5,600 products containing methylene chloride, also a toxic chemical. Kate Gibson, CBS News, 16 Oct. 2023 Her blood toxicity levels were dangerously out of whack with the recipe of strong medication, heat, physical exertion, and lack of water. Ashley Thess, Outdoor Life, 30 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'toxicity.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of toxicity was in 1879

Dictionary Entries Near toxicity

Cite this Entry

“Toxicity.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2023.

Medical Definition


tox·​ic·​i·​ty täk-ˈsis-ət-ē How to pronounce toxicity (audio)
plural toxicities
: the quality, state, or relative degree of being toxic or poisonous

More from Merriam-Webster on toxicity

Last Updated: - Updated example sentences
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