What is of or pertaining to cows; pertaining to, derived from, or caused by, vaccinia; as, vaccine virus; the vaccine disease. -- n. The virus of vaccinia used in vaccination called?

vaccine — Of or pertaining to cows; pertaining to, derived from, or caused by, vaccinia; as, vaccine virus; the vaccine disease. -- n. The virus of vaccinia used in vaccination. (Webster's 1913.)

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