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insidious, sinister, or pernicious?
Few would choose to be associated with people or things that are insidious, sinister, or pernicious; all three of these words have decidedly unpleasant meanings, each with its own particular shade of nastiness.
Insidious comes from a Latin word for “ambush” (insidiae), which is fitting, as this word often carries the meanings “deceitful,” “stealthy,” or “harmful in an imperceptible fashion.” The first two meanings may be applied to people or things (“an insidious enemy,” “an insidious plot”), while the last is usually applied to things (“insidious problems,” “insidious sexism”), in particular to the gradual progress of a disease (“an insidious malignancy”).
Sinister comes from a Latin word meaning “on the left side, unlucky, inauspicious.” Although it is commonly used today in the sense “evil” (“a sinister cult leader”; “a sinister plot”), it may also suggest an ominous foreshadowing of some unfavorable turn of events (“a sinister omen”).
Pernicious has largely stayed true to its etymological root, the Latin noun pernicies “ruin, destruction.” Its original meaning in English, “highly injurious or destructive,” usually applies to things (“pernicious apathy,” “pernicious effects”) and medical conditions (“pernicious fever,” “pernicious anemia”). When applied to people, pernicious means “wicked.”
Synonyms
Examples of pernicious in a Sentence
Barbara Ehrenreich, Nation, 20 Nov. 1995
The more it [the Papacy] took part in the temporal conflicts with consistently pernicious result, the more impotent among the monarchs it revealed itself …
—Barbara W. Tuchman, The March of Folly, 1984
At its most pernicious, paper entrepreneurialism involves little more than imposing losses on others for the sake of short-term profits for the firm.
—Robert B. Reich, Atlantic, March 1983
More pernicious still has been the acceptance of the author's controversial ideas by the general public.
the pernicious effects of jealousy
She thinks television has a pernicious influence on our children.
Jeffrey Sonnenfeld, Fortune, 2 Feb. 2023
Most of us can agree the world is in a perilous state, with natural disasters multiplying, pernicious new viruses continually emerging, the planet steadily overheating, and wars raging in constant rotation.
—David Rooney, The Hollywood Reporter, 1 Feb. 2023
Its release also underscored the pernicious influence of misinformation in the United States, where some influential voices on the right had spread conspiracy theories about the attack on Mr. Pelosi.
—Tim Arango, New York Times, 27 Jan. 2023
Trust your soul-saving instincts against the pernicious intentions of a self-serving industry.
—Armond White, National Review, 25 Jan. 2023
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Cite this Entry
“Pernicious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pernicious. Accessed 22 Nov. 2024.
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pernicious
adjective
Medical Definition
pernicious
adjective
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