Definition of vaccinia
1 or vaccinia virus : a poxvirus (species Vaccinia virus of the genus Orthopoxvirus) that differs from but is closely related to the viruses causing smallpox and cowpox and that includes a strain used in making vaccines against smallpox
2 : a reaction to smallpox vaccine prepared from live vaccinia virus that may involve a rash, fever, headache, and body pain
vaccinialplay \vak-ˈsi-nē-əl\ adjective
Recent Examples of vaccinia from the Web
The vaccine used to eradicate smallpox--the world's oldest vaccine--is itself a living virus named vaccinia; it was first used in 1796 by Edward Jenner, an English doctor.
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Medical Definition of vaccinia
2 or vaccinia virus : a poxvirus of the genus Orthopoxvirus (species Vaccinia virus) that differs from but is closely related to the viruses causing smallpox and cowpox and that includes a strain of uncertain natural origin used in making vaccines against smallpox
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