Edward Waymouth Reid FRS (11 October 1862, Canterbury – 10 March 1948, Edinburgh) was a British physiologist.
Born the fourth son of James, Reid, F.R.C.S.B., E. Waymouth Reid was educated at Sutton Valence Grammar School and then matriculated in 1879 at the University of Cambridge, where he graduated B.A. in 1883 (from Cavendish College which became Homerton College). At St Bartholomew's Hospital in 1885 he qualified M.B. and M.R.C.S. and was an assistant electrician there. At St Mary's Hospital he was a demonstrator in physiology from 1885 to 1887 and a lecturer in physiology from 1887 to 1889.
At the early age of twenty-seven he was appointed to the newly established chair of physiology in University College, Dundee, where he joined a body of highly gifted men who held teaching posts in the recently formed College affiliated to the University of St. Andrews. Waymouth Reid served the University for forty-six years, and after his retirement in 1935 the University of St. Andrews conferred upon him an honorary degree of LL.D.
Waymouth Reid was elected F.R.S. in 1898 and graduated Sc.D. in 1904 from Downing College, Cambridge. He was Dean of the Medical Faculty of the University of St Andrews.
From 1887 to 1905 Reid at St Mary's and Dundee was an active research worker on subjects dealing with physical and electrical phenomena associated with living tissue. At St Mary's with Waller he investigated electrical activity in the excised mammalian heart, published in the Philosophical Transactions of the Royal Society, 1887. Reid invented a recording osmometer, and at Dundee investigated secretion and absorption and the processes of diffusion, osmosis and filtration in the passage of materials across surfaces.
Reid's work in the early 1900s on active transport across biological membranes was not fully appreciated until the 1950s.