booster

noun

boost·​er ˈbü-stər How to pronounce booster (audio)
: 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

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
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
As for the Super Heavy booster, SpaceX lost contact with the lower-stage during its descent about six minutes after launch. Eric Lagatta, USA Today, 9 Oct. 2025 Touchdown Club projects To meet and maintain Carroll’s lofty athletic standards, booster clubs needed to raise significant funds to complete upgrades and facility improvements. Charles Baggarly october 9, Fort Worth Star-Telegram, 9 Oct. 2025 In the era of NIL, schools have to weigh their budget for sports as a way to keep from slipping into irrelevance, which could hurt donations from boosters and enrollment. Jordan Sigler, MSNBC Newsweek, 8 Oct. 2025 For older kids, a booster of the tetanus and pertussis vaccine is typically required, as well as a vaccine for meningococcal disease. David Higgins, The Conversation, 7 Oct. 2025 See All Example Sentences for booster

Word History

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of booster was in 1888

Browse Nearby Words

Cite this Entry

“Booster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/booster. Accessed 14 Oct. 2025.

Kids Definition

booster

noun
boost·​er ˈbü-stər How to pronounce booster (audio)
1
: one that boosts
2
: an enthusiastic supporter
3
4
: a device for strengthening radio or television signals
5
: the first stage of a multistage rocket providing force for the launching and the first part of the flight

Medical Definition

booster

noun
boost·​er ˈbü-stər How to pronounce booster (audio)
: a substance or dose used to renew or increase the effect of a drug or immunizing agent: such as
a(1)
(2)
b
: synergist sense 1
a chemical acting as a booster to sulfa drugs

More from Merriam-Webster on booster

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