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

Jimmer Fredette, Bobby Brown and Royce White are playing, while Frank Mason III and Anthony Tolliver, who spent last season with the Detroit Pistons, are listed as boosters. Noel Harris, sacbee, "How Matt Barnes and others with ties to the Kings are vying to win $2 million," 14 June 2018 With primary races settled in the battleground state Tuesday, Democrats are betting an anti-Trump backlash will carry them to victory in November and are portraying GOP nominees as boosters of Trump, not Nevada — a state Hillary Clinton won in 2016. Washington Post, "Trump to be central in Nevada races for Senate, governor," 13 June 2018 Think of Venus in Leo as a booster shot for any preexisting spring-and-summer fever: Frisky and attention-seeking vibes will abound and inhibitions will be lowered., "What Venus Has In Store For Your Summer Love Life," 11 June 2018 Musk is presumably talking about the upper stage of the two-stage Falcon 9 rocket that serves as the workhorse booster for SpaceX launches. Tariq Malik,, "Elon Musk Says SpaceX Will Try to Land a Rocket with a 'Giant Party Balloon'," 16 Apr. 2018 Last season's champions will draw upon August's 2-1 away win over Spurs as a confidence booster heading into this one., "Chelsea vs Tottenham Preview: Classic Encounter, Recent Form, Team News, Prediction & More," 31 Mar. 2018 And with cameras positioned all over the rocket, viewers got to witness every single aspect of the flight — including the launch, the simultaneous landing of the two outer boosters, and the mannequin’s cruise through Earth orbit. Loren Grush, The Verge, "The Verge 2018 tech report card: SpaceX," 29 Dec. 2018 Instead Conroy wanted to stretch and expand the Stratocruiser's fuselage to transport rocket boosters and other bulky space hardware by plane. David Hambling, Popular Mechanics, "Why the Super Guppy Is Such a Badass Plane," 17 Dec. 2018 This is no easy feat in an increasingly crowded market of boosters offering service to geostationary transfer orbit. Eric Berger, Ars Technica, "Rocket Report: Firefly to the Moon, SpaceX makes a splash, H3 nets a customer," 7 Dec. 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

19 Mar 2019

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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



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

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


to corrupt or become corrupted

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