delusory

Delusory is an adjective used to describe something that is deceptive or based on a delusion, presenting a false or misleading impression of reality. In everyday language, it often refers to beliefs, perceptions, or assurances that feel real but are not supported by evidence, such as a delusory sense of security or a delusory advantage.

Etymology and form: The word derives from the Latin deludere, meaning to mislead or mock, with the English suffix -ory forming adjectives. The term has been in use since the early modern period to convey the idea of belief or appearance that is not trustworthy.

Usage and context: In psychology and psychiatry, delusory beliefs are those held with strong conviction despite clear contradictory evidence, and they are a hallmark of delusions in various mental health conditions. Outside clinical settings, delusory is used more informally to describe ideas or perceptions that mislead or misrepresent reality. It is related but not identical to illusory; illusory typically refers to perceptual mistakes, whereas delusory emphasizes belief and conviction, even in the face of disconfirming information. The two terms can overlap when a perceptual illusion leads to a mistaken belief.

Examples: A delusory sense of superiority, a delusory correlation between two events, or a delusory belief about personal invulnerability.

See also: delusion, illusion, cognitive bias, misperception.