frustrate: [15] Frustrate comes from Latin frūstrātus ‘disappointed, frustrated’, the past participle of a verb formed from the adverb frūstrā ‘in error, in vain, uselessly’. This was a relative of Latin fraus, which originally meant ‘injury, harm’, hence ‘deceit’ and then ‘error’ (its English descendant, fraud [14], preserves ‘deceit’). Both go back to an original Indo- European *dhreu- which denoted ‘injure’. => fraud