undeceived v free from deception or illusion s freed of a mistaken or misguided notion Usage(s) Those who feared that the maestro's great days were over were soon undeceived. Others, undeceived by the play's pretenses, by its dreary smut, by its fairly frequent lapses into complete and trite absurdity, by long stretches in which author e. Last week they were undeceived. Synonym(s) undeceive disabused Antonym(s) deceive