George Johnstone Stoney (15 February 1826 – 5 July 1911) was an Irish physicist known for introducing the term electron as the "fundamental unit quantity of electricity".

[1] Stoney continued his independent scientific research throughout his decades of non-scientific employment duties in Dublin.

Additionally, he intermittently served on scientific review committees of the British Association for the Advancement of Science from the early 1860s on.

He estimated the number of molecules in a cubic millimetre of gas, at room temperature and pressure, from data obtained from the kinetic theory of gases.

In 1891, he proposed the term "electron" to describe the fundamental unit of electrical charge,[7] and his contributions to research in this area laid the foundations for the eventual discovery of the particle by J. J. Thomson in 1897.

[9] Stoney was elected a Fellow of the Royal Society in June 1861 on the basis of being the author of papers on "The Propagation of Waves", "On the Rings seen in Fibrous Specimens of Calc Spar", and Molecular Physics, published in the Transactions of the Royal Irish Academy, et cetera, Distinguished for his acquaintance with the science of Astronomy & General Physics.

Hermann Weyl made a notable attempt to construct a unified theory by associating a gravitational unit of charge with the Stoney length.

Stoney's most scientifically notable relative was his nephew, the Dublin-based physicist George Francis FitzGerald (1851–1901).

In addition, on political matters, both Stoney and FitzGerald were active opponents of the Irish Home Rule Movement.

Stoney resigned from his job as Secretary of Queen's University of Ireland in 1882 in objection to a government decision to introduce "sectarianism" into the system; i.e., Stoney wanted to keep the system non-denominational, but the government acceded to Irish Catholic demands for Catholic institutions.