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

Maezawa, who founded online fashion store Zozotown, bought seats for himself and a handful of artists on SpaceX’s Big Falcon Rocket, which combines a massive, 40-story rocket booster and the Big Falcon Spaceship. Rachel Becker, The Verge, "SpaceX’s Moon loop will affect passengers’ health — here’s how," 18 Sep. 2018 That doesn’t include the various boosters and administrators who pop by, or the students who get a glimpse of drills while walking to class. Ross Dellenger,, "Like the Rest of College Football, the SEC Is Still Building Its Game Plan for Sports Betting," 5 June 2018 Got typhoid and tetanus boosters in afternoon and have felt rotten ever since. Phoebe Wall Howard, Detroit Free Press, "Service Diary of a Corpsman: Roy L. Wall, LST 509," 28 May 2018 Obviously, years of mediocrity haven’t adversely affected the bottom line of the nation’s wealthiest athletic department, but fans and boosters were restless a few years ago. Nick Moyle, San Antonio Express-News, "Big 12 baseball title shows Texas is finding its way back to prominence," 22 May 2018 Fischer expressed a similar view during an ESPN radio appearance last week, saying that enticing the NBA would largely rest on the shoulders of local boosters and the private sector rather than Louisville taxpayers. Phillip M. Bailey, The Courier-Journal, "Taxpayers won't have to pay to bring NBA to Louisville, Dan Issel says," 9 May 2018 Part of the story includes city boosters and volunteers giving away thousands of rose cuttings named after mysterious French dressmaker Madame Caroline Testout. Janet Eastman,, "See why Portland's called the 'City of Roses' at Oregon Historical Society exhibit (photos, video)," 8 May 2018 Giuliani, 73, has been one of Trump’s biggest public boosters and gave a keynote speech at the GOP convention after Trump won the Republican presidential nomination in 2016. Zachary Fryer-biggs, Vox, "Rudy Giuliani is Trump’s new lawyer. His history with Comey could spell trouble.," 20 Apr. 2018 After word leaked out that Schiano was on the verge of being hired Nov. 26, strong backlash among fans, boosters and students led to the offer being pulled. Creg Stephenson,, "Documents released by Tennessee trace wild football coaching search," 23 Mar. 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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Statistics for booster

Last Updated

10 Dec 2018

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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

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to enclose within walls

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