In Jainism, par-parivād is one of the 18 pāpa (sins). It means:

• taking pleasure in others’ sinful acts,
• feeling unhappy when someone does virtuous or good conduct,
• and gossiping or speaking negatively about others. ( jainknowledge.com)

In simple words, it is faulty speech and mindset toward others’ good or bad conduct. It is avoided because it increases karma bondage and harms the purity of thought, speech, and conduct. ( jainknowledge.com)

If you want, I can also explain all 18 pāpa in simple Jain language.