Sir Geoffrey Jefferson FRS (1886–1961) was a British neurologist and pioneering neurosurgeon. He was educated in Manchester, England, obtaining his medical degree in 1909. He became a fellow of the Royal College of Surgeons two years later. He married in 1914, and moved to Canada. On the outbreak of World War I, he returned to Europe and worked at the Anglo-Russian Hospital in Petrograd, Russia, and then with the Royal Army Medical Corps in France.
After the war, he returned to Manchester, working at the Salford Royal Hospital. It was here, in 1925 that Jefferson performed the first successful embolectomy in England. By 1934, he was a neurosurgeon at the Manchester Royal Infirmary, becoming the UK's first professor of neurosurgery at the University of Manchester five years later. The Jefferson fracture, which he was the first to describe, was named after him. Manchester Royal Infirmary also honours Jefferson with the Jefferson Suite, a training area in their Medical Education Campus.
Jefferson was elected a fellow of the Royal Society in 1947. He was awarded the Lister Medal in 1948 for his contributions to surgical science. The corresponding Lister Oration, given at the Royal College of Surgeons of England, was not delivered until 1949, and was titled 'The Mind of Mechanical Man'. The subject of this lecture was the Manchester Mark 1, one of the earliest electronic computers, and Jefferson's lecture formed part of the early debate over the possibility of artificial intelligence. In 1956 he presented the Sir Hugh Cairns Memorial Lecture at the Society of British Neurological Surgeons. 
- So That Was Life: A Biography of Sir Geoffrey Jefferson, Master of the Neurosciences and Man of Letters, Peter H. Schurr, Royal Society of Medicine Press, 1997
- Walshe, F. M. R. (1961). "Geoffrey Jefferson. 1886-1961". Biographical Memoirs of Fellows of the Royal Society 7: 127–126. doi:10.1098/rsbm.1961.0010.
- Botterell, E. H. (1961). "Sir Geoffrey Jefferson 1886–1961". Journal of Neurosurgery 18 (3): 407–400. doi:10.3171/jns.1961.18.3.0407.
- Guthkelch, A. N. (1987). "Geoffrey Jefferson (1886–1961), neurosurgeon, physiologist, philosopher". Journal of Neurosurgery 66 (5): 642–647. doi:10.3171/jns.1987.66.5.0642. PMID 3553452.
- "Announcements". Nature 162 (4108): 138. 1948. doi:10.1038/162138e0.
- Jefferson, G. (1949). "The Mind of Mechanical Man". British Medical Journal 1 (4616): 1105–1110. PMC 2050428. PMID 18153422.
- Hodges, Andrew (1983). Alan Turing: the enigma. New York: Simon and Schuster. ISBN 0-671-49207-1.
- Sir Geoffrey Jefferson, MD, biography from The Society Of Neurological Surgeons
- Sir Geoffrey Jefferson, biography from Who Named It?
- Dobson, R. (2005). "Ozone depletion will bring big rise in number of cataracts". BMJ 331 (7528): 1292–1295. doi:10.1136/bmj.331.7528.1292-d. PMC 1298891.
- Articles relating to Geoffrey Jefferson, from Unbound MEDLINE