Deleterious | Definition of Deleterious by Merriam-Webster

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del·​e·​te·​ri·​ous | \ ˌde-lə-ˈtir-ē-əs \

Definition of deleterious

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

Other Words from deleterious

deleteriously adverb

deleteriousness noun

Synonyms & Antonyms for deleterious



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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 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 Like Facebook and Twitter, YouTube faces similar problems of balancing its enormous earnings and cultural influence with its clearly deleterious effects. Navneet Alang, TheWeek, "Why YouTube is the true successor to TV," 7 Feb. 2020 Too often surgery and hospitalization, Dr. Aronson argues, are not the answer for older patients; and drugs that might be effective on younger adults can have deleterious effects on the elderly. Joseph Epstein, WSJ, "‘Elderhood’ Review: The Way We Age Now," 17 Jan. 2020 Moving away from police response to quality-of life issues or having to leave lower-priority calls to attend to higher-priority calls may have a deleterious effect on police legitimacy. David Squier Jones, Twin Cities, "David Squier Jones: To cure violence, St. Paul needs best practices, not just best politics," 10 Dec. 2019 The group wants the city council to declare a climate crisis and work with members of the indigenous and Pacific Islander communities, which students say are the first to feel the deleterious effects of such things as rising sea levels. oregonlive, "‘The sea is rising and so are we:’ Portland students walk out of class, demand action on climate," 7 Dec. 2019 But in a cash-dependent country like India, the dearth of currency notes proved deleterious, resulting in long lines at bank branches and ATMs, and even some deaths. Nupur Anand, Quartz, "A look into India’s first digital village," 5 Nov. 2019 Some Republican donors and officials worried that Trump's decision would trap them in an untenable situation and have deleterious effects around the world. Author: Seung Min Kim, Josh Dawsey, Anchorage Daily News, "Pullout order followed days of agitation by president," 14 Oct. 2019 But the case study amply demonstrates the importance of properly cleaning such homes, since trace contamination can have a deleterious effect on young children in particular. Jennifer Ouellette, Ars Technica, "Home buyers, beware: Contamination from cooking meth can linger for years," 9 Oct. 2019

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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Cite this Entry

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

More Definitions for deleterious

del·​e·​te·​ri·​ous | \ ˌdel-ə-ˈtir-ē-əs \

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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