In 1779 the English illustrator John Frederick Miller included a coloured plate of the secretarybird in his Icones animalium et plantarum and coined the binomial name Falco serpentarius. As the oldest published specific name, serpentarius has priority over later scientific names. The species 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".