Question: The Duchess of Cornwall uses her title instead of what other title, the title held by the first wife of Prince Charles?

full_context: Document 1: Prince William, Duke of Cambridge: Prince William, Duke of Cambridge, {'1': ", '2': ", '3': ", '4': "} (William Arthur Philip Louis; born 21 June 1982) is the elder son of Charles, Prince of Wales, and Diana, Princess of Wales. He is second in the line of succession to the British throne, after his father.
Document 2: Camilla, Duchess of Cornwall: Camilla, Duchess of Cornwall, ("née" Camilla Rosemary Shand, previously Parker Bowles; born 17 July 1947), is the second wife of Charles, Prince of Wales, the eldest child and heir apparent of Queen Elizabeth II. Instead of using the title of Princess of Wales, she uses the title Duchess of Cornwall, her husband's secondary designation. In Scotland, she is known as the Duchess of Rothesay. In the event of Charles acceding to the throne, Camilla would become a queen consort; however, an official statement issued by Clarence House on the day of her marriage to Charles announced that she would be known as the Princess Consort.
Document 3: Louise de Kérouaille, Duchess of Portsmouth: Louise Renée de Penancoët de Kérouaille, Duchess of Portsmouth (September 1649 – 14 November 1734) was a mistress of Charles II of England. Through her son by Charles II, Charles Lennox, 1st Duke of Richmond, she is ancestress of both wives of Prince Charles: Diana, Princess of Wales, and Camilla, Duchess of Cornwall.
Document 4: Diana, Princess of Wales: Diana, Princess of Wales (Diana Frances; "née" Spencer; 1 July 1961 – 31 August 1997), was a member of the British royal family as the first wife of Charles, Prince of Wales, who is the eldest child and heir apparent of Queen Elizabeth II.
Document 5: Duchess of Cambridge: Duchess of Cambridge is the principal courtesy title held by the wife of the Duke of Cambridge. The title is legally gained upon marriage and is forfeited upon divorce. Five of the eight Dukes of Cambridge did not marry or morganate, and thus there are only three Duchesses of Cambridge including the current Duchess, Catherine, wife of Prince William, Duke of Cambridge.
Document 6: Margaret Hanmer: Margaret Hanmer (c. 1370 – c. 1420), sometimes known by her Welsh name of Marred ferch Dafydd, was the wife of Owain Glyndŵr. Although some modern histories have accorded Margaret the title "Princess of Wales", there is no contemporary record that Margaret used either that title, or her husband's earlier title of Prince of Powys; it is likely Margaret would have used neither. "Princess of Wales", an English honorific given to the wife of the English prince of Wales, was first used by Joan of Kent. Only one wife of a Welsh prince is known to have used the title: Eleanor de Montfort, wife of Llywelyn ap Gruffudd, the last Prince of Wales.
Document 7: Princess of Wales: Princess of Wales (Welsh: "Tywysoges Cymru" ) is a British courtesy title held by the wife of the Prince of Wales, who is, since the 14th century, the heir apparent of the English or British monarch. The first acknowledged title holder was Eleanor de Montfort, wife of Llywelyn ap Gruffudd. It has subsequently been used by wives of post-conquest princes of Wales.
Document 8: Duchess of Rothesay: Duchess of Rothesay is a Scottish courtesy title. It is held by the wife of the Duke of Rothesay since the first Duke in 1398. Due to the mortality rate and the fact that very few Dukes of Rothesay were of majority or married prior to ascending the throne (if that), there have in fact been only eight Duchesses of Rothesay. A separate Scottish throne has not existed "de facto" since 1603 when James VI of Scotland acceded to the throne of England when the House of Tudor died out, creating a personal union. The Act of Union of 1707 united de jure the separate kingdoms and thrones into the Kingdom of Great Britain. Ever since 1603 the title of the Duchess of Rothesay is held by the Princess of Wales, who was also the Duchess of Cornwall; the title of Duchess of Rothesay is for her use when in Scotland.
Document 9: Princess Charlotte of Cambridge: Princess Charlotte of Cambridge (Charlotte Elizabeth Diana; born 2 May 2015) is the younger child and only daughter of Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge. She is fourth in line of succession to the British throne, after her paternal grandfather, her father, and her elder brother.
Document 10: Duke of Rothesay: Duke of Rothesay (Scottish Gaelic: "Diùc Baile Bhòid" , Scots: "Duik o Rothesay" ) is a dynastic title of the heir apparent to the British throne, currently Prince Charles. It was a title of the heir apparent to the throne of the Kingdom of Scotland before 1707, of the Kingdom of Great Britain from 1707 to 1801, and now of the United Kingdom of Great Britain and Northern Ireland. It is the title mandated for use by the heir apparent when in Scotland, in preference to the titles "Duke of Cornwall" (which also belongs to the eldest living son of the monarch, when and only when he is also heir apparent, by right) and "Prince of Wales" (traditionally granted to the heir apparent), which are used in the rest of the United Kingdom and overseas. The Duke of Rothesay also holds other Scottish titles, including those of Earl of Carrick, Baron of Renfrew, Lord of the Isles and Prince and Great Steward of Scotland. The title is named after Rothesay on the Isle of Bute, Argyll and Bute, but is not associated with any legal entity or landed property, unlike the Duchy of Cornwall.
Document 11: Princess consort: Princess consort is an official title or an informal designation normally accorded to the wife of a sovereign prince. The title may be used for the wife of a king if the more usual designation of queen consort is not used.
Document 12: Charles, Prince of Wales: Charles, Prince of Wales (Charles Philip Arthur George; born 14 November 1948) is the eldest child and heir apparent of Queen Elizabeth II. Known alternatively in Cornwall as Duke of Cornwall and in Scotland as Duke of Rothesay, he is the longest-serving heir apparent in British history, having held the position since 1952. He is also the oldest person to be next in line to the throne since Sophia of Hanover (the heir presumptive to Queen Anne), who died in 1714 at the age of 83.
Document 13: Duchess of York: Duchess of York is the principal courtesy title held by the wife of the Duke of York. The title is gained with marriage alone and is forfeited upon divorce. Three of the eleven Dukes of York either did not marry or had already assumed the throne prior to marriage, whilst two of the dukes married twice, therefore there have been only ten Duchesses of York. It is said that the positions of Duke and Duchess of York are charmed, because the title is created every time, or these women become queen consorts.
Document 14: Duchess of Cornwall: The Duchess of Cornwall is the title held by the wife of the Duke of Cornwall. Duke of Cornwall is a non-hereditary peerage held by the British Sovereign's eldest son and heir.
Document 15: Catherine, Duchess of Cambridge: Catherine, Duchess of Cambridge (Catherine Elizabeth "Kate"; "née" Middleton; born 9 January 1982) is the wife of Prince William, Duke of Cambridge. Following his father Charles, Prince of Wales, William is second in line to succeed his grandmother, Queen Elizabeth II, as monarch of the United Kingdom and 15 other Commonwealth realms, making Catherine a likely future queen consort.
ground_truth: Princess of Wales