Definition of deleterious
: harmful often in a subtle or unexpected way deleterious effects deleterious to health
deleterious was our Word of the Day on 05/31/2011. Hear the podcast!
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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.
Recent Examples of deleterious from the Web
A largely atheistic or agnostic Germany also has few religious worries about Islamic immigrants, given that secular affluence and leisure long ago proved far more deleterious to German Christianity than did radical Islam.
Government agencies find no deleterious effects on human health.
The bills prompted sharp attacks by Democrats, who said the legislation would have a deleterious effect on public safety and would ramp up fear among law-abiding immigrants.
The party shares with Islamist groups the idea that society’s deviation from religious values has had a deleterious effect on it.
A new study of elementary-age children shows that those who were not part of an after-school exercise program tended to pack on a particular type of body fat that can have deleterious impacts on brain health and thinking.
More than half of those responding to the online poll also said his tweets could have a deleterious effect on the nation's national security interests.
Arlington adopted its first smoking ordinance in 1985 and amended it in 1991 to restrict smoking in restaurants, which didn’t have the deleterious effect that some had feared.
Attending a low-quality childcare program has deleterious effects on boys, so much so that the children would have been better off staying home.
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.
Origin and Etymology of deleterious
Greek dēlētērios, from dēleisthai to hurt
First Known Use: 1643See Words from the same year
Synonym Discussion of deleterious
DELETERIOUS Defined for English Language Learners
Definition of deleterious for English Language Learners
: damaging or harmful
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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