A. V. Hill, christened Archibald Vivian (which names he detested) CH OBE FRS (26 September 1886 – 3 June 1977) was an English physiologist, one of the founders of the diverse disciplines of biophysics and operations research. He shared the 1922 Nobel Prize in Physiology or Medicine for his elucidation of the production of heat and mechanical work in muscles.

Born in Bristol, he was educated at Blundell's School and graduated from Trinity College, Cambridge as third wrangler in the mathematics tripos before turning to physiology. His early work involved the characterization of what came to be known as Michaelis-Menten kinetics and the use of the Hill coefficient. Hill's first paper, published in 1909 while working under the supervision of John Newport Langley, is a landmark in the history of receptor theory.

Hill made many exacting measurements of the physics of nerves and muscles. His earliest experiments on the heat production of contracting muscles used equipment obtained from the Swedish physiologist Magnus Blix. Both before and after World War I he worked on a range of topics in physiology in cooperation with colleagues in Cambridge, Germany and elsewhere.