The Dutch naturalist Arnout Vosmaer described the secretarybird in 1769 based on a live specimen that had been sent to Holland from the Cape of Good Hope two years earlier by an official of the Dutch East India Company. Vosmaer suggested that the species was called “Sagittarius” because its gait was thought to resemble an archer’s. He also mentioned that it was known as the “Secretarius” by farmers who had domesticated the bird to combat pests around their homesteads and proposed that the word “Secretarius” might be a corruption of “Sagittarius”. In 1779 the English illustrator John Frederick Miller included a plate of the secretarybird in his Icones Animalium et Plantarum and coined the binomial name Falco serpentarius. It was assigned to its own genus Sagittarius in 1783 by the French naturalist Johann Hermann in his Tabula Affinitatum Animalium. The generic name Sagittarius is Latin for “archer”, and the specific epithet serpentarius is from Latin serpens meaning “serpent” or “snake”. The secretarybird is considered as monotypic: no subspecies are recognised.