William Martin Geldart CBE (7 June 1870 – 12 February 1922) was a British jurist.

Edmund Martin Geldart, he was educated at Whitgift School, Croydon; St Paul's School, and Balliol College, Oxford, where he was a scholar and in 1890 won the Gaisford Prize for Greek Verse.

He was a member of the Hebdomadal Council from 1905 and chairman of the university's Delegacy for Women Students from 1911 until it was dissolved in 1921.

[4] Geldart was the author of the influential Elements of English Law (1911), still in print under the title Introduction to English Law (Oxford University Press, 11th edition, ed.

According to one review "Geldart has over the years established itself as the standard account of English law..."[4] He also coedited Aristophanes Comoediae, a 1906–1907 edition of the comedies of Aristophanes, with Frederick William Hall.