1. to think about someone or something constantly in a way that is not normal or healthy
Usage: often used with ‘over’ or ‘about’
2. to completely fill someone’s mind so they cannot think of anything else
Usage: often used in passive voice

Examples

• She tends to obsess over small details.
• He obsessed about his appearance before the interview.
• The mystery obsessed the detective for months.
• Don’t obsess about things you can’t control.
• The idea of failure obsessed him completely.
• She was obsessed with becoming famous.
• The case obsessed the entire police department.