Honoria Lucasta Delagardie, Dowager Duchess of Denver, is a character in the Lord Peter Wimsey novels of Dorothy L. Sayers. She is the widow of the late Mortimer Gerald Wimsey, 15th Duke of Denver, and mother of his children Gerald Christian Wimsey, 16th Duke of Denver, Lady Mary Wimsey, and of course Lord Peter Wimsey himself.
The Dowager Duchess is placed as a member of the Wold Newton Family by Philip José Farmer in Tarzan Alive (where her husband's Dukedom tends to be referred to as 'Pomver'). Her parents are given as Francis Delagardie and Lucasta Rutherford.