del·​e·​te·​ri·​ous | \ ˌde-lə-ˈtir-ē-əs How to pronounce deleterious (audio) \

Definition of deleterious

: harmful often in a subtle or unexpected way deleterious effects deleterious to health

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Other Words from deleterious

deleteriously adverb
deleteriousness noun

Choose the Right Synonym for deleterious

pernicious, baneful, noxious, deleterious, detrimental mean exceedingly harmful. pernicious implies irreparable harm done through evil or insidious corrupting or undermining. the claim that pornography has a pernicious effect on society baneful implies injury through poisoning or destroying. the baneful notion that discipline destroys creativity noxious applies to what is both offensive and injurious to the health of a body or mind. noxious chemical fumes deleterious applies to what has an often unsuspected harmful effect. a diet found to have deleterious effects detrimental implies obvious harmfulness to something specified. the detrimental effects of excessive drinking

Examples of deleterious in a Sentence

In developing countries, the imposition of boundaries around national parks and protected areas has been deleterious for both people and wildlife. — Kristin B. Gunther, Association of American Geographers, 2002 Most everyone now knows the action of pressing mouse keys is far more deleterious to the tender structures of the wrist and hand than typing is. — Michael Finley, Albany (New York) Times-Union, 2 Sept. 1998 This skewed allocation of resources away from those most in need, in turn, insures that many young people from low-income families will continue to be shut out of the economy, with obvious deleterious family and social consequences. — Iris C. Rotberg, Education Week, 9 Mar. 1994 For as James Keirans pointed out to me, ticks are the world's most notorious carriers of the agents of diseases that strike animals, wild and domestic. And they rank second only to mosquitoes in their deleterious effect on humans. — Edwards Park, Smithsonian, January 1987 The chemical is deleterious to the environment. The drug has no deleterious effects on patients.
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Recent Examples on the Web That assessment is no surprise to one professional journalist in Tehran, who has recorded the deleterious impact of rising prices, and now the pandemic, on Iran’s social fabric. Scott Peterson, The Christian Science Monitor, "Why Iranians, rattled by suicides, point a finger at leaders," 8 July 2020 That video of Derek Chauvin pressing his knee into George Floyd’s neck for nearly nine minutes could have deleterious mental health impacts on the Black community. Candice Wang, Popular Science, "Resharing videos of violence against Black people can spark more trauma," 3 July 2020 So the deleterious effects associated with weight gain tend to show up at lower absolute weights for them. Christine Gorman, Scientific American, "Could a Few Extra Pounds Help You Live Longer?," 10 May 2016 Automation may have the most deleterious impact on black men 35 and younger with only a high school diploma, McKinsey said. Khristopher J. Brooks, CBS News, "Why automation could hit black workers harder than other groups," 10 Oct. 2019 Shutdowns have caused financial stress at Tesla and other companies as public health authorities attempt to balance protecting people from spread of the disease with the deleterious economic effects of business closure. Los Angeles Times, "Elon Musk threatens to move Tesla headquarters to Nevada or Texas over shutdown," 9 May 2020 Experts across the fields of psychology, medicine, public policy, sociology, law, and neuroscience have extensively argued that solitary has severe, lasting, and deleterious effects. Saida Grundy, The Atlantic, "Why Boredom Affects Us So Much," 17 Apr. 2020 In the past, their estimates were often too high, because some deleterious mutations tend to disappear over time. Kai Kupferschmidt, Science | AAAS, "Measles may have emerged when large cities rose, 1500 years earlier than thought," 30 Dec. 2019 These numbers obfuscate a darker reality: the deleterious effect of art fairs on small and medium-size galleries. Brian P. Kelly, WSJ, "The High Cost of Art Fairs," 3 Mar. 2020

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

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First Known Use of deleterious

1643, in the meaning defined above

History and Etymology for deleterious

Greek dēlētērios, from dēleisthai to hurt

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Time Traveler for deleterious

Time Traveler

The first known use of deleterious was in 1643

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Last Updated

16 Jul 2020

Cite this Entry

“Deleterious.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2020.

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More Definitions for deleterious


How to pronounce deleterious (audio)

English Language Learners Definition of deleterious

formal : damaging or harmful


del·​e·​te·​ri·​ous | \ ˌdel-ə-ˈtir-ē-əs How to pronounce deleterious (audio) \

Medical Definition of deleterious

: harmful often in a subtle or an unexpected way the deleterious effects of radiation and chemotherapy on the marrow— Christine Gorman deleterious genes

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