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

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 The same first-stage booster launched the planet-hunting Tess satellite in April. Washington Post, "SpaceX launches AI robot, strong coffee for station crew," 29 June 2018 Both the Stage One boosters to be used on this mission and the Dragon capsule have been used on prior missions, according to Sarah Gray, Fortune, "Here's How to Watch the Last Launch of SpaceX's Block 4 Falcon 9," 29 June 2018 But a student who has not yet received the booster may still attend school by providing a temporary certificate from a doctor, said JCPS spokeswoman Toni Konz-Tatman. Emma Austin, The Courier-Journal, "JCPS students have more time to get hepatitis A vaccine," 26 June 2018 During the assembly, DiVincenzo spent most of her time recognizing student achievement as well as contributions by board members, the PSA, the boosters and the Rev. Vincent Costello. Steve Sadin,, "Students find new academic homes as Holy Cross closes," 11 June 2018 Without the boosters and the people who support Seminole Athletics, we athletes wouldn’t be able to get an education. Mike Bianchi,, "Exploitation of athletes? FSU softball star Jessie Warren sings a different song," 9 June 2018 The charges also say the boosters covered her travel and lodging on the band trips., "Three Northshore High band instructors face ethics charges," 30 May 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

3 Sep 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

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