də̇ˈlüzhən, dēˈ- noun
( -s )
Etymology: Middle English delusioun, from Latin delusion-, delusio, from delusus (past participle of deludere to delude) + -ion-, -io -ion — more at delude
1. : act of deluding or state of being deluded ; often : a misleading of the mind
such pleasures end in delusion
: an abnormal mental state characterized by occurrence of delusions
2. : something that is falsely or delusively believed or propagated : false belief or a persistent error of perception occasioned by false belief or mental derangement : customary or fixed misconception
cling to a delusion
as
a. : a false conception and persistent belief unconquerable by reason in something that has no existence in fact
b. : a false belief regarding the self or persons or objects outside the self that persists despite the facts and is common in paranoia, schizophrenia, and psychotic depressed states
delusions of grandeur