Jenner is an English surname-name from an occupational term for an engineer or maker of engines.
Jenner is an English occupational surname repurposed as a given name, derived from the Middle English *gynour* or *enginner* — itself from Old French *engigneur*, meaning an engineer or designer of military engines and siege works. In the Middle Ages, an "engineer" was specifically a craftsman who built ingenious mechanical devices, and the surname Jenner attached itself to families in this trade. As an English topographic and occupational surname, it is documented from at least the thirteenth century, clustering particularly in the south of England.
The name's most historically significant bearer was Edward Jenner (1749–1823), the English physician who developed the world's first vaccine — the smallpox vaccine — through his legendary observations of milkmaids and cowpox. Jenner's discovery is considered one of the greatest achievements in medical history, ultimately leading to the eradication of smallpox in 1980 and establishing the entire field of immunology. His name therefore carries one of the most extraordinary legacies in the history of science, associated with ingenuity, observation, and the saving of hundreds of millions of lives.
In the twenty-first century, Jenner gained enormous contemporary visibility through the Jenner-Kardashian family, particularly Caitlyn Jenner (formerly Bruce Jenner, Olympic decathlon champion) and model Kendall Jenner, making it a surname thoroughly familiar in popular culture. As a given name, Jenner has the strong, crisp quality of the new wave of surname-names — confident, gender-flexible, and carrying an unexpected depth for those who know its history.