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 Adam Laxalt, the former attorney general of Nevada until 2019 and booster for President Donald Trump, believed he was exposed to the coronavirus while attending the Conservative Political Action Conference in Maryland. Brett Murphy, USA TODAY, "When COVID testing was scarce, CDC director called in favor to help Nevada GOP leader," 19 Sep. 2020 Police came up with the charge after finding a WiFi booster in a search of Micah’s home. Zecharias Zelalem, Quartz Africa, "Ethiopia has started clamping down on independent media again as tensions rise," 16 Sep. 2020 The large version of Starship would be coupled with a Super Heavy booster with 37 Raptor engines combined for Mars colonization plans. Richard Tribou,, "SpaceX prepping for next level of Starship tests," 10 Sep. 2020 On Monday, SpaceX founder Elon Musk said engineers have tweaked the design of the Super Heavy booster by increasing the thrust of its Raptor engines. Eric Berger, Ars Technica, "Rocket Report: Musk updates Super Heavy plan, China to launch spaceplane?," 4 Sep. 2020 Wednesday's firing of Flight Support Booster 1, the sixth test of a five-segment SLS booster since 2009, was intended to collect engineering data on the performance of new materials and equipment that may be incorporated in downstream SLS flights. William Harwood, CBS News, "Solid fuel booster for NASA's new moon rocket test fired in Utah," 2 Sep. 2020 As with the flu shot, an extra strong dose or some kind of booster may be needed. Claudia Wallis, Scientific American, "Why Some People Get Terribly Sick from COVID-19," 20 Aug. 2020 The scenario in which the government forces a morality booster upon everyone is far-fetched. Parker Crutchfield, The Conversation, "‘Morality pills’ may be the US’s best shot at ending the coronavirus pandemic, according to one ethicist," 10 Aug. 2020 In 1990, the NCAA put Illinois on probation for rules violations, including improper contacts with recruits and improper car loans to players from a team booster. Washington Post, "Lou Henson, basketball coach who took two teams to Final Four, dies at 88," 31 July 2020

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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Time Traveler for booster

Time Traveler

The first known use of booster was in 1888

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Statistics for booster

Last Updated

24 Sep 2020

Cite this Entry

“Booster.” Dictionary, Merriam-Webster, Accessed 26 Sep. 2020.

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More Definitions for booster


How to pronounce booster (audio)

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
b : synergist sense 1 a chemical acting as a booster to sulfa drugs

More from Merriam-Webster on booster

Thesaurus: All synonyms and antonyms for booster

Nglish: Translation of booster for Spanish Speakers

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