Definition of vaccine

What does the word vaccine mean?

• part of speech: adjective, noun

  Of cows or cowpox or vaccination; (n.) virus of cowpox as used in vacination (bovine, humanized, v., got direct from cow, got from human subject), modified virus of any disease similarly used, whence vaccinal, vaccinic, aa.; v.-farm (where v. is cultivated by inoculation of heifers); v. -point, pointed instrument used in inoculation. [French]