Duncan is a Scottish surname. The Scottish Gaelic name Donncheann or Donnchadh are bynames composed of the elements donn, meaning "brown" or "dark" from Donn a Gaelic God; and chadh, meaning "chief" or "noble".^[1][2][3] In some cases when the surname was used in County Sligo, Ireland, it is an Anglicized form of the Irish Gaelic name MacDonough or Mac Donnchadha and Ó Duinnchinn, meaning "descendant of Donncheann". The surname Duncan is represented in Scottish Gaelic as MacDhonn.

Acting

• Carmen Duncan (1942–2019), Australian actress
• Lindsay Duncan (born 1950), British actress
• Michael Clarke Duncan (1957–2012), American actor
• Sandy Duncan (born 1946), American actress

Art and design

• Charles Stafford Duncan (1892–1952), San Francisco painter and lithographer.
• Edward Duncan (1803–1882), British watercolourist
• Jane Duncan (architect) (born 1953), British architect
• Jean Duncan (artist) (1933–2018), British artist
• Walter Duncan (1848–1932), British painter

Military, armed forces

• Adam Duncan (1731–1804), British admiral
• Donald B. Duncan (1896–1975), American vice-admiral
• Donald W. Duncan (1930–2009), American soldier and anti-war activist
• Henry Duncan (1735–1814), British naval officer
• Pippa Duncan, British naval officer
• W. G. G. Duncan Smith (1914–1996), British military aviator

Music

• C Duncan, born Christopher Duncan, Scottish composer and musician whose debut album Architect was nominated for the 2015 Mercury Prize
• Gary Duncan (1946–2019), American guitarist and singer
• Johnny Duncan (country singer) (1938–2006), American singer
• Lesley Duncan, English singer and songwriter
• Little Arthur Duncan (1934–2008), American blues harmonica player, singer, and songwriter
• Molly Duncan (1945–2019), Scottish tenor saxophonist
• Tim Duncan (singer), Southern Gospel singer
• Trevor Duncan, English composer
• Zélia Duncan, Brazilian singer and songwriter

Politics

• Alan Duncan (born 1957), British politician
• Arne Duncan (born 1964), U.S. Secretary of Education (2009–2015)
• Charles Duncan Jr. (1926–2022), U.S. Secretary of Energy (1979–1981)
• Frank I. Duncan (1858–1946), American politician, lawyer, judge and newspaper publisher
• Jimmy Duncan, (born 1947), American politician, U.S. Representative from Tennessee's 2nd congressional district (1988–2019)
• John Duncan Sr., (1919–1988), American politician, U.S. Representative from Tennessee's 2nd congressional district (1965–1988), father of Jimmy Duncan
• Kirsty Duncan (born 1966), Canadian politician and Deputy Leader of the Government in the House of Commons
• Leslie Duncan (1880–1952), newspaper editor and politician in South Australia
• Mike Duncan (born 1951), chairman of the Board of Governors of the United States Postal Service and former chairman of the Republican National Committee in the United States
• Peter Duncan (Australian politician) (born 1945), Labor representative in South Australian and federal parliaments
• Peter Duncan (British politician) (born 1965), Scottish politician, Member of Parliament from Galloway and Upper Nithsdale (2001–2005)
• Sir Walter Gordon Duncan (1885–1963), South Australian pastoralist and MLC
• Walter Hughes Duncan (1848–1906), South Australian pastoralist and MHA for Burra
• Walter Leslie Duncan (1883–1947), Australian Senator for New South Wales
• Wesley Duncan (b. 1980), American politician, Member of the Nevada Assembly
• William Addison Duncan (1836–1884), U.S. Representative from Pennsylvania's 19th congressional district (1883–1984)

Sports

• Alexander Duncan (1884-1959), British long-distance runner
• Alex Duncan (1900–1984), Australian rules football player
• Andy Duncan (basketball) (1922–2006), American basketball player
• Bobby Duncan (born 1945), Scottish footballer
• Bobby Duncan (footballer, born 2001)
• Cecil Duncan (1893–1979), Canadian ice hockey administrator
• Chris Duncan (1981-2019), American baseball player
• Dave Duncan (baseball) (born 1945), Major League Baseball player and pitching coach, father of Chris Duncan and Shelley Duncan
• Darryl Duncan, Australian rugby league footballer
• Eric Duncan (born 1984), American baseball coach
• George Duncan (golfer) (1883–1964), Scottish golfer
• Ian Duncan (born 1961), Kenyan rally driver
• Jaelyn Duncan (born 2000), American football player
• Jean Duncan (umpire), Scottish hockey umpire
• Jeff Duncan (baseball) (born 1978), American baseball player and coach
• John Duncan (footballer) (1949–2022), Scottish footballer who notably played for Dundee and Tottenham Hotspur
• Johnny Duncan (footballer) (1896–1966), Scottish international footballer and manager, who was most notably with Leicester City
• Jon Duncan (born 1975), British orienteer
• Jonathan Duncan (swimmer) (born 1982), New Zealand swimmer
• Katie Duncan (born 1988), New Zealand association footballer
• Ken Duncan (American football) (born 1946), American football player
• Mariano Duncan (born 1963), Dominican baseball player
• Rick Duncan (born 1941), American football player
• Ross Duncan (born 1944), Australian cricketer
• Sam Duncan, Westmeath Gaelic footballer
• Scott Duncan (footballer) (1888–1976), former Scottish football player and manager
• Shelley Duncan, American baseball player
• Tim Duncan (born 1976), American basketball player
• Vern Duncan (1890–1954), American baseball player

Writers

• Alasdair Duncan, Australian writer
• Dave Duncan (writer) (1933–2018), Canadian writer
• Glen Duncan (born 1965), British author
• Isabelle Wight Duncan (1812–1878), Scottish author
• Jane Duncan (1910–1976), pseudonym of Scottish writer Elizabeth Jane Cameron
• Lois Duncan (1934–2016), American writer of children's books
• Mary Lundie Duncan (1814–1840), Scottish poet and hymn-writer
• Robert Duncan (poet), U.S. beat poet

Other fields

• Bruce Duncan (born 1938), British priest and founder
• Carl Porter Duncan (1921–1999), professor of experimental psychology at Northwestern University, US
• Dan Duncan (1933–2010), American businessman
• David Duncan, government witness in the Enron scandal
• David Douglas Duncan (1916–2018), American photojournalist
• David F. Duncan, epidemiologist and drug policy adviser to former US president Bill Clinton
• Donald F. Duncan Sr., American entrepreneur and inventor, most commonly associated with Yo-yos
• Gary Duncan, defendant in case Duncan v. Louisiana decided by the US Supreme Court
• George Smith Duncan, a tramway and mining engineer
• Graham Duncan (botanist), botanist at Kirstenbosch Botanic Garden, South Africa
• Helen Duncan (1897–1956), Scottish medium
• Henry Duncan (minister), founder of the first Trustee Savings Bank
• Herbert Osbaldeston Duncan (1862–1945), English racing bicyclist, journalist, and pioneer of the British automobile industry
• Iain Duncan Smith, British politician
• Isadora Duncan, American dancer
• Jonathan Duncan (currency reformer) (1799–1865), British advocate of reforming the monetary system
• Jonathan Duncan (Governor of Bombay) (1756–1811)
• Joseph Edward Duncan (1963–2021), American convicted serial killer and child molester
• Kath Duncan (1888 or 1889 – 1954), Scottish communist activist
• Ken Duncan (photographer) (born 1954), Australian photographer
• Leslie Duncan (1880–1952), newspaper editor and politician in South Australia
• Mary Ellen Duncan (died 2022), American academic administrator and teacher
• Mike Duncan (podcaster), U.S. history podcaster and writer
• Pearl Duncan, Australian retired teacher, anthropologist, academic and Aboriginal elder.
• Scott Duncan (businessman), American billionaire
• Stephen Duncan (1787–1867), American plantation owner in the Antebellum South
• Stewart Duncan (philosopher), American philosopher
• Thomas Eric Duncan (1972–2014), first Ebola victim of the 2014 West African outbreak to develop symptoms while in the US
• Vender Duncan (1928–1959), American serial killer
• Walter Jack Duncan (1881–1941), war artist for the US Army during World War I
• Warren W. Duncan (1857–1938), American jurist
• William Duncan (American physician) (1860–1900), American physician and politician
• William Duncan (philosopher) (1717–1760), Scottish natural philosopher and classicist

Fictional characters

• Karen Beecher-Duncan, supporting character (and sometime member) of the Teen Titans (DC Comics)
• Lily Duncan, a fictional character from Mona the Vampire
• Mal Duncan, supporting character (and sometime member) of the Teen Titans (DC Comics)
• Tammy & Tommy Duncan, supporting characters from The Mighty Ducks.
• Tyler Duncan and Mrs. Duncan are secondary characters in Big Time Rush
• Veronica Duncan, supporting character in Young Sheldon
• Ian Duncan, a character in the TV series Community, played by actor John Oliver
• King Duncan, of Shakespeare's Macbeth
• Duncan, (Walter Sparrow) Robin of Locksley's companion in the 1991 film Robinhood Prince of Thieves.
• Duncan Idaho, a Mentat from Frank Herbert's Dune
• Tara Duncan, the titular character of the French fourteenth-book series by Sophie Audouin-Mamikonian. Unfortunately, only the first two have been translated into English.