Undeceiver
Noun
Plural: undeceivers
accent: undeceiver
Etymology: from the verb undeceive, the analysis of which is un- (prefix), de- (prefix) and capere (= to take). SEE all English vocables derived from, or compounded with, Latin stems of capere at the entry UNACCEPTANCE, in this UNHYPOCRITICAL ENGLISH DICTIONARY.
Definition: one who or that which undeceives.
Equivalent periphrases in other idioms: personne détrompant, qui desabuse, in French; desengañador, in Spanish; disingannatore/trice, in Italian.
[…] these tales of poisonous brides have a three-character plot featuring deceiver, deceived, and undeceiver. Gillian Bennett (Bodies)
By a gesture I imposed silence on Marian, who was about to speak –as I thought it was better to allow the old man to be his own undeceiver.
The Knickerbocker, vol. 53