Donald Ninian Nicol JP DL (3 October 1843 – 27 July 1903)^[1] was a British barrister and politician, who served as the Unionist Party MP for Argyllshire 1895 to 1903.^[2]

Nicol was born in Liverpool, Lancashire, in October 1843 to a Scottish father & English mother. He was educated in Scotland, first at Merchiston Castle School, Edinburgh and at the University of Glasgow. In 1863 he entered Queen's College, Oxford, achieving a BA in 1867 and an MA in 1872. He was called to the bar at the Middle Temple in 1870 and worked on the Northern Circuit.^[3]

Nicol stood for election as the Conservative candidate for Argyllshire in the 1895 general election, where he defeated the incumbent Liberal MP Donald Horne Macfarlane.^[4] Nicol was re-elected at the 1900 general election with a 54% majority.

Nicol was married to Anne Millicent Bates (1849-1946), daughter of Sir Edward Bates, in 1874.^[5] They had 4 children.

Nicol suffered from heart disease in later life, and he died in July 1903 after suffering a severe illness.^[2] He was succeeded as MP in a by-election by Liberal candidate Sir John Ainsworth who Nicol had previously defeated in 1900.