Cách sử dụng
The word 'pernicious' is used to describe something that is harmful or has a negative effect, especially when it is subtle or gradual. It is often used to describe things like bad habits, harmful ideas or beliefs, or poisonous substances. You might use it to describe something that you think is causing harm, or to warn someone about something that could be dangerous in the long term. For example, "Smoking is a pernicious habit that can lead to serious health problems over time."