delusional

Everyday

1. (medicine) A delusional person firmly believes things that are not true, even when shown clear proof, often because of an illness. tree →
2. (informal) Delusional means having very unrealistic hopes or ideas about yourself or a situation. tree →

In the lessons

In medicine and mental health, delusions can be a symptom of illness, and the person needs care and kindness, not mockery. In everyday talk and banter, «You're delusional!» is said jokingly to someone who thinks their team will win everything. Phrases: «delusional thinking», «completely delusional».

Examples

• The doctor said the patient was delusional and needed treatment. tree →
• You're delusional if you think we'll win 10–0! tree →
• The delusional king believed he could fly. tree →
• He was delusional about how good his singing was. tree →
• Illness can make a person delusional, so they need help. tree →
• It's delusional to think you can pass without revising. tree →

Note

Noun: delusion (a false belief). Do not confuse with illusion (a false impression of the eyes or mind, like a magic trick). Calling someone delusional can be hurtful if they are really ill.