as in harmful
causing or capable of causing harm
the pernicious effects of illegal narcotics on society
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Example Sentences
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Recent Examples of pernicious
Microplastics are tiny fragments, that can be as small as 1/25,000th of an inch (1 micrometer) and are a pernicious part of the plastic pollution crisis.
—
Laura Paddison,
CNN Money,
29 Apr. 2026
What is more pernicious than the denial is the tacit acceptance of his behavior in the community, as the community was the lifeblood of his art.
—
Doreen St. Félix,
New Yorker,
25 Apr. 2026
And that’s not all — Yeon’s new film about the pernicious undead has set its North American theatrical release date.
—
Abid Rahman,
HollywoodReporter,
14 Apr. 2026
That may sound like a smart countermeasure to a pernicious tech shortcut.
—
Nathan Agranovsky,
Washington Post,
13 Apr. 2026
See All Example Sentences for pernicious
Laura Paddison,
CNN Money,
29 Apr. 2026
What is more pernicious than the denial is the tacit acceptance of his behavior in the community, as the community was the lifeblood of his art.
—
Doreen St. Félix,
New Yorker,
25 Apr. 2026
And that’s not all — Yeon’s new film about the pernicious undead has set its North American theatrical release date.
—
Abid Rahman,
HollywoodReporter,
14 Apr. 2026
That may sound like a smart countermeasure to a pernicious tech shortcut.
—
Nathan Agranovsky,
Washington Post,
13 Apr. 2026
See All Example Sentences for pernicious
Recent Examples of Synonyms for pernicious
Adjective
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The plasma process also produced very little smoke or tar, reducing harmful secondary pollutants typically associated with biomass conversion and making the technology a cleaner way to produce renewable solid fuel.
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At the same time, its flowers attract beneficial predatory insects, such as ladybugs and parasitic wasps, that naturally hunt harmful garden pests.
Adjective
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Others develop dangerous fluctuations in blood pressure and abnormal heart rhythms because the autonomic nervous system becomes affected.
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Sometimes, the streets appear glittering; other times, seedy and dangerous.
Adjective
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According to 24/7 Wall Street, the $60 billion all-stock AI company Anysphere acquisition, a $20 billon debt offering, and the future end of the lockup have been particularly detrimental to the maintenance of the share prices.
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There’s also the thought that onboarding a starting catcher midseason can be detrimental to a pitching staff, something that Yankees general manager Brian Cashman has expressed in the past.
Adjective
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Each specimen was weighed and put in the same-sized containers filled with superworm larvae to determine the optimal ratio of larvae to specimen for thorough cleaning without damaging bones.
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And such a gap can be far more damaging than any technology shortfall.
Adjective
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In pharmacogenomics, understanding how genes affect drug efficacy helps doctors prescribe the right drug at the optimal dose while reducing adverse reactions.
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Johnson was undone by revelations of his conduct during Covid lockdowns and Truss by the adverse market reaction to her 2022 mini-Budget.
Cite this Entry
“Pernicious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/pernicious. Accessed 3 Jul. 2026.
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