as in harmful
causing or capable of causing harm
the pernicious effects of illegal narcotics on society
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Recent Examples of pernicious
By being seen as seriously pursuing domestic reform, the Administration may be able to garner deals for the phasing out of particularly pernicious ACMDs.
—
Alden Abbott, Forbes.com, 21 Aug. 2025
Air pollution of all forms can be detrimental to health, but the tiny particles in smoke are particularly pernicious.
—Bloomberg, Mercury News, 13 Aug. 2025
Many scandals arise from the occasion of these activities, and adulteries and other outrageous crimes are committed as a clear offence to God, a very serious danger to the souls of those committing them, and a pernicious example to others.
—The Editors, JSTOR Daily, 27 Mar. 2025
One of the most pernicious forms of homegrown mass violence is school shootings.
—Patrik Jonsson, The Christian Science Monitor, 21 Mar. 2025
See All Example Sentences for pernicious
Alden Abbott, Forbes.com, 21 Aug. 2025
Air pollution of all forms can be detrimental to health, but the tiny particles in smoke are particularly pernicious.
—Bloomberg, Mercury News, 13 Aug. 2025
Many scandals arise from the occasion of these activities, and adulteries and other outrageous crimes are committed as a clear offence to God, a very serious danger to the souls of those committing them, and a pernicious example to others.
—The Editors, JSTOR Daily, 27 Mar. 2025
One of the most pernicious forms of homegrown mass violence is school shootings.
—Patrik Jonsson, The Christian Science Monitor, 21 Mar. 2025
See All Example Sentences for pernicious
Recent Examples of Synonyms for pernicious
Adjective
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Researchers in Indonesia have unveiled a ‘dazzling breakthrough’ that transforms plastic waste into glowing nanomaterials capable of sensing harmful substances in water.—
Sujita Sinha,
Interesting Engineering,
24 Sep. 2025
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These statements are harmful and untrue, Chabot said.—
Madeline Mitchell,
USA Today,
24 Sep. 2025
Adjective
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This neurological response evolved to keep our ancestors alive in genuinely dangerous situations.—
Anne-Laure Le Cunff,
Big Think,
29 Sep. 2025
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In hilly terrain there are hundreds of low water crossings which are potentially dangerous in heavy rain.—
CA Weather Bot,
Sacbee.com,
29 Sep. 2025
Adjective
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Overwatering mums is just as detrimental as underwatering.—
Kim Toscano,
Southern Living,
30 Sep. 2025
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Trump warned that major changes could occur — which could be detrimental to Democrats — if the government runs out of funding.—
Brendan Rascius,
Miami Herald,
30 Sep. 2025
Adjective
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Speaking to reporters for the first time since the opener, Prince on Friday took responsibility for the late substitutions that contributed to two damaging delay of game penalties late in the Week 2 loss against the Patriots.—
Barry Jackson,
Miami Herald,
26 Sep. 2025
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In just a matter of hours, damaging winds and record-breaking flooding started to devastate many areas, especially the higher terrains of the southeastern Appalachians.—
Sam Gillette,
PEOPLE,
26 Sep. 2025
Adjective
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Drinking it less often, enjoying it with meals or rinsing your mouth out with water after drinking may lessen such adverse effects.—
Daryl Austin,
USA Today,
26 Sep. 2025
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And no serious adverse events were reported.—
Jacqueline Howard,
CNN Money,
26 Sep. 2025
Cite this Entry
“Pernicious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/pernicious. Accessed 1 Oct. 2025.
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