Perniciouscausing great harm in a harmful way that may not be obvious is an adjective for something that causes serious harm, especially in a way that is not obvious at first. It can describe a direct destructivecausing damage or ruin effect or a hiddennot easily seen or noticed one that spreads quietly over time.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Pronunciation
AI-generated pronunciation audio (OpenAI).
Accent: General American English
IPA: /pər-NISH-əs/
Easy pronunciation: per-NISH-əs (approximate spelling).
Stress: Stress the second syllable.
Adjective meaning harmful in a hidden or gradual way.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Pernicious Meaning
harmful in a quiet, hard-to-notice way
Part of speech: adjective
Definition: working or spreading in a hidden and usually injurious way
Example: The report warned about the pernicious effects of misinformation on public trust.
Synonyms for this meaning:
- insidious — A strong fit when the harm is gradual or not immediately obvious.
- subtle — Can fit the hidden aspect, but it is broader and does not always imply harm.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Other Meanings of Pernicious
Meaning 2
very harmful or destructive
Part of speech: adjective
Definition: exceedingly harmful
Example: The disease had a pernicious effect on the community.
Synonyms for this meaning:
- baneful — A close match for strongly harmful or damaging.
- deadly — Works in some contexts, but it more often means causing death directly.
- pestilent — Can mean very harmful, but it is less common and more literary.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Pernicious Synonyms
Similar Meaning
- insidious
very harmful or destructive
- baneful
- deadly
- pestilent
Reviewed with OpenAI Decisions. Assessment: uncertain — manual review needed. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Common Mistakes
- Using pernicious to mean merely annoying or unpleasant. It implies real harm, not just something negative.
- Treating subtle as a full synonym in every context. It can mean hidden or hard to notice, but it does not always mean harmful.
- Using deadly as if it always means pernicious. Deadly usually suggests causing death, while pernicious can describe broader harm.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
Frequently Asked Questions
What does pernicious mean in simple English?
It means very harmful, often in a way that is not easy to see right away.
Is pernicious a positive or negative word?
It is strongly negative. It describes something damaging or dangerous.
What is the closest synonym for pernicious?
Insidious is often the closest match when the harm is hidden or gradual. In stronger harmful contexts, baneful can also fit.
Can pernicious mean deadly?
Sometimes, but not exactly. Deadly usually means causing death, while pernicious can mean harmful in a broader sense.
Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-11-02. AI assessment; not a guarantee of accuracy.
