de·lu·sion 
/dɪˈlu:ʒən/ noun
plural de·lu·sions /dɪˈlu:ʒən/ noun [count] 1 : a belief that is not true : a false idea
▪ He has delusions about how much money he can make at that job. ▪ He is living/laboring under the delusion that he is incapable of making mistakes. ▪ She is under the delusion that we will finish on time. 2 : a false idea or belief that is caused by mental illness
▪ As the illness progressed, his delusions took over and he had violent outbursts. ◊If you have delusions of grandeur, you believe that you are much more important than you really are.
▪ The patient is suffering from hallucinations and delusions of grandeur. ▪ a young actress with delusions of grandeur
▪ He has delusions about how much money he can make at that job. ▪ He is living/laboring under the delusion that he is incapable of making mistakes. ▪ She is under the delusion that we will finish on time.
▪ As the illness progressed, his delusions took over and he had violent outbursts. ◊If you have delusions of grandeur, you believe that you are much more important than you really are.
▪ The patient is suffering from hallucinations and delusions of grandeur. ▪ a young actress with delusions of grandeur
— de·lu·sion·al /dɪˈlu:ʒənl̟/ adjective [more delusional; most delusional]
▪ He showed signs of delusional thinking near the end of his life. ▪ If you think we can afford a new car, you are delusional.
/dɪˈlu:ʒənl̟/ adjective [more delusional; most delusional] ▪ He showed signs of delusional thinking near the end of his life. ▪ If you think we can afford a new car, you are delusional.
