What does pernicious mean from the story Romeo and Juliet?

In the context of Romeo and Juliet, "pernicious" means harmful, destructive, or deadly. It is used to describe the effects of love, which can be both passionate and destructive. In the play, the love between Romeo and Juliet is so intense that it leads to their downfall. Their relationship is ultimately doomed because of the feud between their two families, and their love for each other is seen as a threat to the social order. In this sense, the love between Romeo and Juliet is seen as a "pernicious" force that ultimately leads to their tragic end.