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

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. See More
Recent Examples on the Web But her presence could have other deleterious effects. Daniel Strauss, The New Republic, 10 Aug. 2022 Just being involved with such a firm can also have deleterious long-term reputational effects on the careers of attorneys and accountants who worked there. Jay Adkisson, Forbes, 8 Aug. 2022 While tariffs may be a hypothetical future bargaining chip, the deleterious impact of such tariffs on a U.S. economy in crisis is already being felt across the board. Jason Oxman, Fortune, 19 July 2022 Death has a more deleterious impact on the environment than many realize. William Ralston, Wired, 26 July 2022 Such high quit rates have become so deleterious that companies are flagging the Great Resignation as a potential business risk in their annual reports. Phil Wahba, Fortune, 28 Apr. 2022 The Defense Department suggests that the lack of in-person engagement throughout the pandemic has had a deleterious effect on recruiting; that seems more plausible. WSJ, 4 Aug. 2022 But the rise of benzos has also had deleterious effects in a country that is still in the grips of a deadly opioid epidemic. Julyssa Lopez, Rolling Stone, 5 July 2022 The people who might most benefit from this book—those who have bought into the myth of paradise with an ocean view, deleterious impact be damned, and have the means to regularly experience a version of it—don’t want their illusions destroyed. Lauren Groff, The Atlantic, 21 June 2022 See More

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.

First Known Use of deleterious

1587, in the meaning defined above

History and Etymology for deleterious

Greek dēlētērios, from dēleisthai to hurt

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The first known use of deleterious was in 1587

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Last Updated

27 Sep 2022

Cite this Entry

“Deleterious.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2022.

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More Definitions for deleterious


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

More from Merriam-Webster on deleterious

Nglish: Translation of deleterious for Spanish Speakers

Britannica English: Translation of deleterious for Arabic Speakers


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