Meaning of the word pernicious in English

What does pernicious mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

pernicious

US /pɚˈnɪʃ.əs/
UK /pəˈnɪʃ.əs/

Adjective

having a harmful effect, especially in a gradual or subtle way

Example:
The pernicious influence of social media on young minds is a growing concern.
He suffered from a pernicious disease that slowly weakened him.