1. a viral disease of cattle that produces pustules on the udder, used to make smallpox vaccine
Usage: medical; veterinary
2. the virus that causes this disease, used in smallpox vaccination
Usage: medical; scientific

Examples

• Vaccinia was first observed in dairy cattle by farmers.
• Edward Jenner used vaccinia to develop the first smallpox vaccine.
• The vaccinia virus is closely related to the smallpox virus.
• Scientists study vaccinia in laboratories for vaccine research.
• Vaccinia pustules appear on infected cattle udders.
• The discovery of vaccinia led to the eradication of smallpox.