adverb
- in a way that causes great harm or damage, especially in a gradual or subtle manner
Usage: formal
Examples
- The false rumors spread perniciously through social media.
- Discrimination can work perniciously to undermine confidence.
- The chemical leaked perniciously into the groundwater over decades.
- His influence operated perniciously behind the scenes.
- The disease progressed perniciously without obvious symptoms.
- Misinformation can perniciously shape public opinion.