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
Full Definition of booster shot
: a supplementary dose of an immunizing agent —called also booster, booster dose
Examples of booster shot in a sentence
He had to get two booster shots at his latest checkup.
First Known Use of booster shot
Medical Definition of booster shot
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