1. to allow yourself to have or do something that you enjoy but that may not be good for you
2. to allow someone to have or do whatever they want, especially when this is not good for them
3. to take part in an activity, especially one that is considered bad or unhealthy

Examples

• She decided to indulge in a piece of chocolate cake.
• Parents shouldn’t indulge their children’s every whim.
• He likes to indulge in expensive hobbies.
• They indulged in gossip about their coworkers.
• I’m going to indulge myself with a spa day.
• The grandparents tend to indulge their grandchildren.
• She refused to indulge in self-pity after the setback.