cowpox

詳細解釋：

cow.pox

n.（名詞）
A mild, contagious skin disease of cattle, usually affecting the udder, that is caused by a virus and characterized by the eruption of a pustular rash. When the virus is transmitted to humans, as by vaccination, it can confer immunity to smallpox.Also called vaccinia
牛痘：牛的一種良性皮膚傳染病，通常感染乳房，由一種病毒引起並出現發膿皰疹症狀。當這一病毒通過種痘等被移植入人體後，它可以產生對天花的免疫力也作 vaccinia