Cowpox
WordNet
noun
(1) A viral disease of cattle causing a mild skin disease affecting the udder; formerly used to inoculate humans against smallpox
WiktionaryText
Noun
- A pustular, eruptive skin disease of cattle caused by an Orthopoxvirus, with lesions occurring principally on the udder and teats. Human infection may occur from touching cows, and gives immunity to smallpox.