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

Anthony Scaramucci, once one of Trump's biggest boosters on the White House staff, has turned on the president and is using his celebrity to rally Republicans against his former boss. Author: Robert Costa, Philip Rucker, Anchorage Daily News, "Trump critics eye GOP primary challenges - even if defeating him seems ‘daunting’," 22 Aug. 2019 Monumental Sports chief executive Ted Leonsis, whose company operates Capital One Arena, has been one of the most enthusiastic boosters for sports betting. Fenit Nirappil, Washington Post, "Sports betting won’t launch in D.C. in time for NFL season; bars start applying," 9 Aug. 2019 The much smaller nine-story test stack consisted of a booster with a dummy version of the Orion spacecraft, designed to match the actual Orion’s weight, 22,000 lbs. Jeffrey Kluger, Time, "With NASA's Orion Abort-System Test, Americans Just Took a Small (and Very Big) Step Closer to the Moon," 2 July 2019 Musk said in a tweet that included pictures of all three boosters. Marcia Dunn, The Seattle Times, "SpaceX launches mega rocket, lands all 3 boosters," 14 Apr. 2019 This is the first time SpaceX was able to successfully land all of Falcon Heavy's three boosters. Avery Thompson, Popular Mechanics, "SpaceX Lands All Three Falcon Heavy Boosters for the First Time," 10 Apr. 2019 Football players at the University of Louisiana are being encouraged to donate to a booster organization that funds the athletic department., "Dale Earnhardt Jr., family OK after airline crash," 17 Aug. 2019 Sierra Nevada engineers and the company's owners, Fatih and Eren Ozmen, considered boosters built in Japan, Europe and by SpaceX and Blue Origin. William Harwood, CBS News, "Dream Chaser spaceplanes to launch on ULA Vulcan rocket," 14 Aug. 2019 Most of the middle-class people have found private solution to a public service water delivery failure by investing in underground tank and booster pumps. Washington Post, "People, companies forced to save water in parched India city," 13 Aug. 2019

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

3 Sep 2019

Look-up Popularity

Time Traveler for booster

The first known use of booster was in 1888

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More Definitions for booster



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
US : someone who supports an idea or organization


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

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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

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recurring in steady succession

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