undeceivable

Undeceivable is a rare English adjective meaning that a person cannot be deceived or fooled. It differs from undeceived, which describes someone who has escaped deception at a particular moment, and from undeceptive, which would mean lacking a deceptive quality. In use, undeceivable usually characterizes a person's judgment, character, or perceptiveness: a negotiator who tests claims and notices inconsistencies may be called undeceivable. The word tends to occur in formal, literary, or deliberately emphatic contexts rather than ordinary modern conversation. It can sound old-fashioned, and saying someone is undeceivable may imply a remarkable or even idealized resistance to manipulation. Because the term is uncommon, clear surrounding context is important when it appears. Nevertheless, it is useful for describing not merely a successful escape from a trick but a stable capacity to recognize and resist deception. The form also illustrates the productive English use of the prefix un- to create an adjective meaning “not” or “unable to be affected by” a quality named by another adjective.

Not capable of being deceived or fooled; impossible to deceive.

Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.

Where does undeceivable come from?

The English adjective was formed by adding the productive prefix un- (“not”) to deceivable (“able to be deceived”). Deceivable derives from Latin decipiere, meaning “to deceive,” from de- and capere, “to take.” The formation follows the familiar English pattern of using un- with an adjective to express the absence or negation of the quality it names.

How undeceivable is actually used

This is a rare, formal or literary word. It usually characterizes a person's judgment, character, or perceptiveness and can sound emphatic, archaic, or hyperbolic in ordinary conversation.

Easily confused with undeceivable

What's the opposite of undeceivable?

Rhymes with undeceivable