1. false beliefs that are firmly held despite evidence to the contrary, especially as symptoms of mental illness
Usage: medical/psychological context
2. mistaken ideas or beliefs that mislead someone
Usage: general usage

Examples

• The patient suffered from delusions that people were following him.
• She had delusions of grandeur, believing she was a famous actress.
• His delusions about easy wealth led to poor financial decisions.
• The medication helped reduce his paranoid delusions.
• Many people have delusions about how quickly they can lose weight.
• Her delusions of persecution made it difficult to maintain friendships.