pernicious
Americanadjective
-
causing insidious harm or ruin; ruinous; injurious; hurtful.
pernicious teachings;
a pernicious lie.
- Synonyms:
- malicious, noxious, baneful, damaging, destructive, deleterious, detrimental, harmful
-
deadly; fatal.
a pernicious disease.
- Synonyms:
- lethal
-
Obsolete. evil; wicked.
adjective
-
wicked or malicious
pernicious lies
-
causing grave harm; deadly
Other Word Forms
Derived Forms
Etymology
Origin of pernicious
First recorded in 1515–25; from Latin perniciōsus “ruinous,” from pernici(ēs) “ruin” (from per- per- + -nici-, combining form of nex “death, murder” + -ēs, noun suffix) + -ōsus -ous
Explanation
Pernicious means harmful and subtle, such as a poison gas that causes illness in those exposed to it over the course of years. Pernicious comes from the Latin perniciosus, "destructive," which in turn comes from pernicies, "death" or "ruin." You might have heard your parents and teachers talk about the pernicious effects of watching too much TV and playing video games all day — they'll turn your brain to mush (allegedly).
Vocabulary lists containing pernicious
Romeo and Juliet
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300 Most Difficult "SAT" Words
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The Tragedy of Hamlet, Prince of Denmark
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
An important first step toward finding answers can be found in a paper cited in the V-Dem report, "Pernicious Polarization, Autocratization and Opposition Strategies."
From Salon • Apr. 3, 2022
The 1939 law was originally titled “An Act to Prevent Pernicious Political Activities.”
From Seattle Times • Nov. 9, 2021
The Hatch Act, also known as the “Act to Prevent Pernicious Political Activities,” was signed into law in 1939 by President Franklin D. Roosevelt.
From Washington Post • Jun. 13, 2019
"Pernicious anemia is an autoimmune disease that starts in the stomach and that impairs the body's ability to absorb food efficiently," physician and medical historian Dr. John Sotos told CBS News.
From US News • Jul. 18, 2016
I am here, as you know, in my official capacity as Chairman of the Pernicious Activities Committee of the North American Senate.
From Triplanetary by Smith, E. E. (Edward Elmer)
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
