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

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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.
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Recent Examples on the Web And in a less flagrant but nonetheless pernicious example of gender dynamics across top MBA programs, women’s grades often lag behind those of men—a reflection of curricula and evaluation systems that work to perpetuate structural inequalities. Sarah Todd, Quartz at Work, "Three MBA admissions heads explain why record numbers of women are going to business school," 21 Nov. 2019 To the founders, this kind of corruption was especially pernicious, and plainly merited impeachment. Arkansas Online, "Panel report lays out case against Trump," 17 Dec. 2019 As PC Gamer recounts, The Outer Worlds developer Taylor Swope recently went into a lengthy explanation of one of the game's most bizarre, pernicious, and hard-to-find bugs. Julie Muncy, Wired, "The New Xbox Has a Name and a Questionable Shape," 13 Dec. 2019 That’s why this retroactivity here is so pernicious. Ephrat Livni, Quartz, "Health insurers fighting claim denials made some seriously ironic arguments at the Supreme Court," 10 Dec. 2019 But the problem is particularly pernicious at the societal scale. The Economist, "Open Future We’re designed to make bad choices but here’s what we can do," 6 Dec. 2019 Those oily foes, which the folks at the MSD call FOG – fats, oils and grease – are particularly pernicious. Mackensy Lunsford, USA TODAY, "You absolutely should not put these Thanksgiving foods in your garbage disposal," 28 Nov. 2019 Add to this the transportation costs of going to the gynecologist’s office almost every day for two weeks to track egg growth—a small but pernicious expense. Gwen Torsky, Health.com, "I Have Terminal Breast Cancer, but I'm Still Spending Thousands of Dollars Each Year on Costs My Insurance Won't Cover," 31 Oct. 2019 But the more pernicious force in the coming months and years might be the extent to which government supporters view military intervention as a solution to Brazil’s economic and security problems. Amy Erica Smith, Mollie Cohen, Matthew Layton, Vox, "Did Brazilians vote against democracy on Sunday?," 30 Oct. 2018

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.

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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

Time Traveler

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

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Statistics for pernicious

Last Updated

22 Jan 2020

Cite this Entry

“Pernicious.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/pernicious. Accessed 22 January 2020.

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More Definitions for pernicious

pernicious

adjective
How to pronounce pernicious (audio)

English Language Learners Definition of pernicious

formal : causing great harm or damage often in a way that is not easily seen or noticed

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

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