boost·er | \ˈbü-stər \

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

That made him a darling of conservative groups, some energy companies and some prominent Republican boosters. Louise Radnofsky, WSJ, "Embattled Scott Pruitt Resigns as EPA Administrator," 5 July 2018 The building’s observation deck offers a stunning view of distant Hong Kong as well as the Pearl River Delta, an expanse that local boosters like to call the Greater Bay Area. Adam Lashinsky, Fortune, "Alibaba v. Tencent: The Battle for Supremacy in China," 21 June 2018 Instead, a booster vehicle typically carries them to a height and altitude where the engine can take over. Kyle Mizokami, Popular Mechanics, "The U.S. Air Force Is Pushing for a Hypersonic Strike Weapon," 11 June 2018 For several years afterward each dog will each receive a booster dose and a physical exam. Keridwen Cornelius, Scientific American, "A Shot against Cancer Slated for Testing in Massive Dog Study," 7 June 2018 Salmon's also a mood booster: Along with offering a good dose of vitamin B6, it's packed with omega-3 fatty acids, which have been found to be effective when treating patients with major depressive disorder. 8. Amy Capetta, Woman's Day, "10 Foods That Fight Off ALL Your PMS Symptoms," 19 June 2015 Some leaks—such as ones at the brake booster—are easy to detect, but others can be notoriously elusive. Mike Allen, Popular Mechanics, "How to Find a Vacuum Leak," 28 Feb. 2011 However, the agency also wants the motor to serve as the main booster for the Vega-C. Loren Grush, The Verge, "Europe will fire its record-setting big solid rocket motor this week," 11 July 2018 Rogozin has already made the decision to retire the Proton booster, preferring to focus on the next-generation Angara rockets. Eric Berger, Ars Technica, "Russian editor: Our space program is entering the “Dark Ages”," 9 July 2018

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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Phrases Related to booster

booster chair

booster cushion

Statistics for booster

Last Updated

15 Oct 2018

Look-up Popularity

Time Traveler for booster

The first known use of booster was in 1888

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More Definitions for booster


boost·er | \ˈbü-stər \

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

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More from Merriam-Webster on booster

Thesaurus: All synonyms and antonyms for booster

Spanish Central: Translation of booster

Nglish: Translation of booster for Spanish Speakers

Comments on booster

What made you want to look up booster? Please tell us where you read or heard it (including the quote, if possible).


to reject or criticize sharply

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