delusion

de·lu·sion

noun \di-ˈlü-zhən\

Definition of DELUSION

1

a : the act of deluding : the state of being deluded b : an abnormal mental state characterized by the occurrence of psychotic delusions

2

: a false belief regarding the self or persons or objects outside the self that persists despite the facts and occurs in some psychotic states—compare hallucination 1, illusion 2a