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 The deaths also happened as Christians of color were in a civil war of faith with white, conservative evangelicals who appeared united with them in core beliefs but divided over politics and how common and pernicious racial prejudice could be. Jaweed Kaleem, Los Angeles Times, "Asian American Christians confront racism and evangelical ‘purity culture’ after Atlanta spa shootings," 6 Apr. 2021 And, most pernicious of all, the league’s new television deal had collapsed; if a replacement could not be found, French domestic soccer was facing ruin. New York Times, "A French Soccer Team Clings to First Place as the Bottom Falls Out," 2 Apr. 2021 But emphasizing it unevenly, or to the exclusion of what unites us, can have pernicious effects. Pradheep J. Shanker, National Review, "The Misleading Narrative about Anti-Asian Racism," 23 Mar. 2021 Yet sometimes gravity’s pernicious influence can get in the way. Karmela Padavic-callaghan, Scientific American, "Ultracold Quantum Collisions Have Been Achieved in Space for the First Time," 19 Mar. 2021 These are pernicious problems that have developed over decades. Mark Zandi For Cnn Business Perspectives, CNN, "Our pandemic nightmare is almost over. We should all thank the US government," 10 Mar. 2021 One of the country’s most pernicious economic challenges is epitomized by its latest political scandal. Mike Bird, WSJ, "Korea’s Big Economic Conundrum: Mo Money, Mo Problems," 12 Mar. 2021 In fact, social media platforms often host content that is far more pernicious than that of their fellow, unprotected electronic publishers. Jeff Bewkes, Fortune, "Now is not the time to repeal Section 230, but it should be soon," 30 Dec. 2020 Familiarity has bred alarm: the book feels, in 2021, more potent, more pernicious, less of a riotous highball and more of a ruinous opioid. Stacy Schiff, The New Yorker, "Véra Nabokov Was the First and Greatest Champion of “Lolita”," 5 Mar. 2021

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

14 Apr 2021

Cite this Entry

“Pernicious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pernicious. Accessed 18 Apr. 2021.

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More Definitions for pernicious

pernicious

adjective

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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