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
Tariffs are particularly pernicious tax hikes and are now the cornerstone of Republican economic policy.
—
Steven Greenhut, Oc Register, 16 Jan. 2026
Punishing Kelly is extremely pernicious political retaliation.
—David A. Graham, The Atlantic, 5 Jan. 2026
Not only does the extant relationship between art and commerce imply no causal relationship between commercial performance and literary quality, but this false implication is itself a pernicious impediment to both the creation and profitable production of great art.
—Literary Hub, 10 Dec. 2025
Some of these efforts spawned even more pernicious phenomena.
—Ray Takeyh, Foreign Affairs, 4 Dec. 2025
See All Example Sentences for pernicious
Steven Greenhut, Oc Register, 16 Jan. 2026
Punishing Kelly is extremely pernicious political retaliation.
—David A. Graham, The Atlantic, 5 Jan. 2026
Not only does the extant relationship between art and commerce imply no causal relationship between commercial performance and literary quality, but this false implication is itself a pernicious impediment to both the creation and profitable production of great art.
—Literary Hub, 10 Dec. 2025
Some of these efforts spawned even more pernicious phenomena.
—Ray Takeyh, Foreign Affairs, 4 Dec. 2025
See All Example Sentences for pernicious
Recent Examples of Synonyms for pernicious
Adjective
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While skepticism toward artificial intelligence is understandable, dismissing AI as inherently harmful overlooks both history and reality.—
Arkansas Online,
Arkansas Online,
27 Jan. 2026
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Regulators will examine whether Grok is living up to its obligations under the Digital Services Act, the bloc’s wide-ranging rulebook for keeping internet users safe from harmful content and products.—
Kelvin Chan,
Chicago Tribune,
26 Jan. 2026
Adjective
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More than a billion phones are now ineligible for security updates at a time when the threat landscape has never been more dangerous.—
Zak Doffman,
Forbes.com,
27 Jan. 2026
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The church opened its warming center over the weekend, anticipating the arrival of the winter storm and the dangerous drop in temperatures.—
Leondra Head,
CBS News,
27 Jan. 2026
Adjective
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The opposite, overwatering, is also detrimental because the seeds may rot.—
Megan Hughes,
Better Homes & Gardens,
28 Jan. 2026
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There’s been tension between the dynamic guard and head coach Tuomas Iisalo and some of that started after the Grizzlies lost to the Lakers in October in which Morant scored only eight points and was later suspended for one game for conduct detrimental to the team for postgame comments.—
Broderick Turner,
Los Angeles Times,
28 Jan. 2026
Adjective
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This is because free iron can catalyze reactive oxygen species, which may prove to be chemically damaging.—
Scott Travers,
Forbes.com,
30 Jan. 2026
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Emily Mendenhall traces the medical myths, gender bias, and neurological truths behind hysteria, one of history’s most damaging diagnoses.—
Big Think,
Big Think,
29 Jan. 2026
Adjective
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Affected cosmetics that are applied to the skin or eyes may lead to skin irritation, infection, or other adverse reactions.—
Michele Laufik,
Martha Stewart,
30 Jan. 2026
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Even for women whose initial mammograms didn’t show any calcium buildup and were considered low risk, risk of an adverse cardiac incident increased by 41% if buildup was detected on followups.—
Helen Carefoot,
Flow Space,
30 Jan. 2026
Cite this Entry
“Pernicious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/pernicious. Accessed 6 Feb. 2026.
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