William Whigham Fletcher FRSE FLS (11 August 1918 – 4 April 2001) was a Scottish biologist and academic author.
He specialised in crop protection and was one of the first to study the environmental impact of herbicides.
Due to this he was immediately mobilised at the outbreak of war and served in first the Royal Army Ordnance Corps and then the Royal Army Medical Corps, serving in Egypt, Libya, Lebanon, Italy, Syria and Greece.
In 1952 he was appointed Head of Botany at the West of Scotland Agricultural College and in 1962 became Senior Lecturer at Glasgow's Royal College of Science and Technology (later renamed Strathclyde University).
His proposers were John Hawthorn, Peter Pauson, Donald Pack and Patrick Dunbar Ritchie.