DUENNA, specifically the chief lady-in-waiting upon the queen of Spain (Span. a married lady or mistress, Lat. doming). The word is more widely applied, however, to an elderly lady in Spanish and Portuguese households (holding a position midway between a governess and companion) appointed to take charge of the young girls of the family; and "duenna" is thus used in English as a synonym for chaperon (q.v.) .