pernicious

adjective
per·​ni·​cious | \ pər-ˈni-shəs How to pronounce pernicious (audio) \

Definition of pernicious

1 : highly injurious or destructive : deadly
2 archaic : wicked

Other Words from pernicious

perniciously adverb
perniciousness noun

Choose the Right Synonym for pernicious

pernicious, baneful, noxious, deleterious, detrimental mean exceedingly harmful. pernicious implies irreparable harm done through evil or insidious corrupting or undermining. the claim that pornography has a pernicious effect on society baneful implies injury through poisoning or destroying. the baneful notion that discipline destroys creativity noxious applies to what is both offensive and injurious to the health of a body or mind. noxious chemical fumes deleterious applies to what has an often unsuspected harmful effect. a diet found to have deleterious effects detrimental implies obvious harmfulness to something specified. the detrimental effects of excessive drinking

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.”

Examples of pernicious in a Sentence

The notion that poll data are a legitimate form of news has to be one of the most pernicious tenets of late-twentieth-century American journalism … — 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. See More
Recent Examples on the Web All the pernicious political effects of social media — siloing, polarization, radicalization — follow from this way of doing business. Damon Linker, The Week, 26 Oct. 2021 While inflation and supply chain woes may explain part of these brands’ profit shortfalls, the underlying troubles appear more pernicious. Steve Dennis, Forbes, 5 May 2022 There’s nothing more pernicious on the collective psyche than having to pay more. Jeff Stein And Evan Halper, Anchorage Daily News, 12 Apr. 2022 Using a barrage of increasingly outlandish falsehoods, President Vladimir V. Putin has created an alternative reality, one in which Russia is at war not with Ukraine but with a larger, more pernicious enemy in the West. New York Times, 20 Mar. 2022 Activists have accused the government of a more pernicious application of technology: the manipulation of a mobile app that categorizes individuals’ risk of COVID infection to prevent them from travelling. Evan Osnos, The New Yorker, 11 Feb. 2022 In fact, the day-to-day operations of many galleries are built around more banal forms of excess that elide easy parody but are equally pernicious. New York Times, 25 Mar. 2022 Putin’s success in seeding some of these misleading narratives through proxies and allies is casting doubt on the ability of Western governments and the tech giants to effectively rein in the most pernicious forms of authoritarian propaganda. Washington Post, 8 Apr. 2022 Baldwin used to say ignorance allied with power is the most pernicious enemy of justice. Los Angeles Times, 8 Mar. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pernicious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of pernicious

15th century, in the meaning defined at sense 1

History and Etymology for pernicious

Middle English, from Anglo-French, from Latin perniciosus, from pernicies destruction, from per- + nec-, nex violent death — more at noxious

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Time Traveler for pernicious

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The first known use of pernicious was in the 15th century

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Dictionary Entries Near pernicious

Pernettya

pernicious

pernicious anemia

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Last Updated

20 May 2022

Cite this Entry

“Pernicious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pernicious. Accessed 26 May. 2022.

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More Definitions for pernicious

pernicious

adjective
per·​ni·​cious | \ pər-ˈni-shəs How to pronounce pernicious (audio) \

Kids Definition of pernicious

: causing great damage or harm a pernicious disease a pernicious habit

pernicious

adjective
per·​ni·​cious | \ pər-ˈnish-əs How to pronounce pernicious (audio) \

Medical Definition of pernicious

: highly injurious or destructive : tending to a fatal issue : deadly pernicious disease

More from Merriam-Webster on pernicious

Nglish: Translation of pernicious for Spanish Speakers

Britannica English: Translation of pernicious for Arabic Speakers

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