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booster shot

noun

Simple Definition of booster shot

  • : an extra amount of a substance (called a vaccine) that is injected with a needle into a person or animal to help protect against a particular disease

Source: Merriam-Webster's Learner's Dictionary

Full Definition of booster shot

  1. :  a supplementary dose of an immunizing agent —called also booster, booster dose


Medical Dictionary

booster shot

noun

Medical Definition of booster shot

  1. :  a supplementary dose of an immunizing agent administered as an injection <… the state is requiring older children to have additional booster shots for measles, mumps and rubella.—Ann Schrader, The Denver Post, 22 July 1997>—see booster, booster dose




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