tox·​ic·​i·​ty | \ täk-ˈsi-sə-tē How to pronounce toxicity (audio) \
plural toxicities

Definition of toxicity

: the quality or state of being toxic: such as
a : 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
b : 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 Roland said the poison center has also received reports of young children getting into CBD products and ending up in emergency rooms with symptoms of THC toxicity. Christina Van Waasbergen, The Arizona Republic, 14 May 2022 However, there are some people who are downright miserable with themselves that try to create toxicity for others. Expert Panel®, Forbes, 13 May 2022 On average, about two-thirds of the eagles the center has taken in annually since 2016 have had positive lead-toxicity levels, according to Alex Wehrung, a spokesman for the group. Dana Hedgpeth, Washington Post, 12 May 2022 The venom from snakes and scorpions may cause toxicity. People Staff,, 5 May 2022 The study claimed around 80 beagle puppies were used in toxicity testing where they were forced daily to ingest a drug via stomach tube for months. Claire Rafford, The Indianapolis Star, 22 Apr. 2022 But the tactics of many of the anti-establishment politicians stem from a similar well of political toxicity. Stephen Collinson, CNN, 12 Apr. 2022 Plants of concern: Wismer and Poppenga recommend that dog owners research specific plants before adding them to their yard; the ASPCA maintains a list of plants and their toxicity to dogs. Washington Post, 4 May 2022 The poison dried into a crystalline substance, and Nelson realized that vaporizing it nullified its toxicity, producing one of the most powerful hallucinogenic agents on Earth. The New Yorker, 21 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'toxicity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of toxicity

1879, in the meaning defined above

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Time Traveler for toxicity

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The first known use of toxicity was in 1879

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toxic jaundice

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Statistics for toxicity

Last Updated

18 May 2022

Cite this Entry

“Toxicity.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for toxicity


tox·​ic·​i·​ty | \ täk-ˈsis-ət-ē How to pronounce toxicity (audio) \
plural toxicities

Medical Definition of toxicity

: the quality, state, or relative degree of being toxic or poisonous

More from Merriam-Webster on toxicity

Nglish: Translation of toxicity for Spanish Speakers


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