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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Teri handled higher-value finds and saw that potentially dangerous items – like firearms and knives – got to the local sheriff’s office.
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Looking back through the sequence, Brazil have good numbers back and there is little need for anyone to overcommit — but a lazy tackle from behind leads to a free kick in a dangerous area.
Adjective
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And beneath the surface of those turquoise waters, marine life continues on without knowing their life is colliding in detrimental-to-them ways.
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Substance abuse is greatly detrimental in its own right, of course, but sometimes the issues that stem from it—stress, emotional exhaustion, secrecy, avoidance—can have similarly devastating long-term effects on a person’s wellbeing.
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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These conditions can increase your vulnerability to adverse effects from poor air quality.
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Valentine also testified that the FDA encourages infant formula companies to send in all adverse event reports and that nothing prevented Mead Johnson from doing so.
Cite this Entry
“Pernicious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/pernicious. Accessed 7 Jul. 2026.
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