working or spreading in a hidden and usually injurious way
“glaucoma is an insidious disease”
Word Forms
deadliness
noun
the quality of being deadly
perniciousness
noun
grave harmfulness or deadliness
pestilence
noun
a pernicious and malign influence that is hard to get rid of
insidiousness
noun
subtle and cumulative harmfulness (especially of a disease)
Around the World
Europe
🇩🇪German
schädlich
überaus schädlich
🇫🇷French
pernicieux
extrêmement nocif
🇪🇸Spanish
pernicioso
extremadamente dañino
🇮🇹Italian
pernicioso
estremamente dannoso
🇳🇱Dutch
verderfelijk
buitengewoon schadelijk
🇵🇹Portuguese
pernicioso
extremamente prejudicial
🇷🇺Russian
пагубный
чрезвычайно вреден
India
🇮🇳Hindi
हानिकारक
अत्यधिक हानिकारक
🇧🇩Bengali
ক্ষতিকর
অত্যন্ত ক্ষতিকর
🇮🇳Tamil
தீங்கு விளைவிக்கும்
மிகவும் தீங்கு விளைவிக்கும்
🇮🇳Telugu
హానికరమైన
అత్యంత హానికరం
🇮🇳Marathi
अपायकारक
अत्यंत हानिकारक
🇮🇳Gujarati
હાનિકારક
અતિશય હાનિકારક
🇮🇳Kannada
ವಿನಾಶಕಾರಿ
ಅತ್ಯಂತ ಹಾನಿಕಾರಕ
🇮🇳Malayalam
വിനാശകരമായ
അത്യന്തം ഹാനികരം
🇮🇳Punjabi
ਨੁਕਸਾਨਦੇਹ
ਬਹੁਤ ਜ਼ਿਆਦਾ ਨੁਕਸਾਨਦੇਹ
🇵🇰Urdu
نقصان دہ
انتہائی نقصان دہ
East & Southeast Asia
🇨🇳Chinese
有害
极其有害
🇯🇵Japanese
有害な
極めて有害な
🇰🇷Korean
유해한
매우 해롭다
🇻🇳Vietnamese
nguy hiểm
cực kỳ có hại
🇹🇭Thai
เป็นอันตราย
เป็นอันตรายอย่างยิ่ง
🇮🇩Indonesian
jahat
sangat berbahaya
🇵🇭Filipino
nakapipinsala
lubhang nakakapinsala
🇲🇾Malay
merosakkan
amat memudaratkan
Middle East
🇸🇦Arabic
خبيث
ضارة للغاية
🇮🇷Persian
مخرب
فوق العاده مضر
🇹🇷Turkish
zararlı
son derece zararlı
🇮🇱Hebrew
מַמְאִיר
מזיק ביותר
Test Yourself1 / 3
What is the primary definition of the word 'pernicious'?
The primary meaning of 'pernicious' is 'exceedingly harmful'.
Which of the following sentences uses the word 'pernicious' in a grammatically correct way?
Using 'pernicious' in a noun/adjective form makes the first sentence correct.
In which domain is the word 'pernicious' most likely to appear as standard vocabulary?
'pernicious' is a standard word used primarily in general literature and formal communications.
Community Poll1 / 6
How often do you encounter the word 'pernicious' in your daily reading?
Very Often
Occasionally
Rarely
Never
Do you find 'pernicious' easy to spell?
Yes, very easy
Somewhat easy
A bit confusing
Extremely hard
In your opinion, does the word 'pernicious' have a positive, neutral, or gloomy tone?
Positive
Neutral
Gloomy
Vibrant
Which age group is most likely to use 'pernicious' in regular conversations?
Kids (3-12)
Teens (13-19)
Adults (20-60)
Seniors (60+)
How likely are you to use 'pernicious' in a professional email?
Very likely
Somewhat likely
Not very likely
Never
Would you classify 'pernicious' as formal, casual, or slang?
Formal
Casual
Slang
Archaic
Pick an option to see how others voted
This word is also in the Advanced book — want the full, immersive treatment (age meanings, culture, creative use, deeper Hindi & exercises)?
Open the Advanced entry →
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