John Dow Fisher Gilchrist (1866–1926) was a Scottish ichthyologist, noted for his work in South Africa. He was born in Anstruther, Fife, Scotland, and died at Saint James, Cape Town, South Africa.
He studied at St. Andrews, Edinburgh, Munich and Zurich, obtaining a Ph.D. at Jena University, Germany in 1894. He studied marine biology in Naples, Monaco and the Isle of Man before returning to teach zoology at the University of Edinburgh. During this time he translated Monismus als Band zwischen Religion und Wissenschaft, by Ernst Haeckel, into English.
John Gilchrist held the post of Professor and Director of Fisheries and Marine Biological Survey of South Africa, in Cape Town.
He is the recognised authority for many genera and species of fish, such as Paralichthodes algoensis, the peppered flounder. His standard abbreviation under the International Code of Zoological Nomenclature is Gilchrist.
The genus Gilchristella, a member of the Clupeidae (herring) family, was named in 1935 in his honour.