booster

noun
boost·​er | \ ˈbü-stər How to pronounce booster (audio) \

Definition of booster

: one that boosts: such as
a : an enthusiastic supporter
b : an auxiliary device for increasing force, power, pressure, or effectiveness
c slang : shoplifter
d : a radio-frequency amplifier for a radio or television receiving set
e : the first stage of a multistage rocket providing thrust for the launching and the initial part of the flight
f : a substance or dose used to renew or increase the effect of a drug or immunizing agent especially : booster shot

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Examples of booster in a Sentence

These exercises are real metabolism boosters. Music is my favorite mood booster. A sincere compliment can be a true confidence booster. The university has a number of wealthy boosters who contribute generously each year. a new design for rocket boosters
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Recent Examples on the Web Further protecting the vaccinated through booster shots. Zachary B. Wolf, CNN, 10 Sep. 2021 As the vaccinations aren’t perfect, a series of future booster shots required and reports of new strains emerging, many employees will continue to be concerned about risks to their health. Jack Kelly, Forbes, 10 Sep. 2021 The state is authorizing COVID-19 booster shots for all residents 65 and older who live in congregate care settings, Gov. Larry Hogan said Wednesday. From Usa Today Network And Wire Reports, USA TODAY, 10 Sep. 2021 But those numbers are also inflated by some Americans seeking out their own additional booster shots. Compiled Democrat-gazette Staff From Wire Reports, Arkansas Online, 10 Sep. 2021 Federal officials are moving ahead with plans to begin administering booster shots of the mRNA vaccines to bolster protection against the more transmissible delta variant. Zeke Miller, Chron, 10 Sep. 2021 The booster shots will be free and available in more than 80,000 locations but the criteria for who should receive them – and when – has not been announced. Leada Gore | Lgore@al.com, al, 10 Sep. 2021 But amid the spread of the more transmissible Delta variant and evidence that vaccine efficacy is waning somewhat, U.S. health officials began developing plans to offer booster shots to increase protection. Leslie Gornstein, CBS News, 10 Sep. 2021 Federal officials are moving ahead with plans to begin administering booster shots of the mRNA vaccines to bolster protection against the more transmissible delta variant. The Salt Lake Tribune, 9 Sep. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'booster.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of booster

1888, in the meaning defined above

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Time Traveler for booster

Time Traveler

The first known use of booster was in 1888

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Dictionary Entries Near booster

boost

booster

booster battery

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Statistics for booster

Last Updated

13 Sep 2021

Cite this Entry

“Booster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/booster. Accessed 21 Sep. 2021.

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More Definitions for booster

booster

noun

English Language Learners Definition of booster

: an action or substance that makes something stronger or more effective
: something that helps or encourages someone or something

booster

noun
boost·​er | \ ˈbü-stər How to pronounce booster (audio) \

Medical Definition of booster

: a substance or dose used to renew or increase the effect of a drug or immunizing agent: such as
a(1) : booster shot
(2) : booster dose
b : synergist sense 1 a chemical acting as a booster to sulfa drugs

More from Merriam-Webster on booster

Nglish: Translation of booster for Spanish Speakers

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