booster

noun

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

Synonyms of booster

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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
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.
The Chinese commercial launch company Landspace is set for a second attempt at catching an orbital booster. — Andrew Jones, Space.com, 7 Aug. 2026 Another real confidence booster is that new brake-by-wire setup. — Howard Walker, Robb Report, 7 Aug. 2026 After launch, the glide vehicle separates from the rocket booster and travels through the atmosphere at speeds above Mach 5 while making course adjustments. — Prabhat Ranjan Mishra, Interesting Engineering, 5 Aug. 2026 While boosters seek to help their favorite team recruit top players and win championships, MMRs are not aligned with any particular school and simply want to turn a profit. — Michael McCann, Sportico.com, 5 Aug. 2026 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

Phrases Containing booster

Rhymes for booster

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Browse Nearby Words

boost
booster
booster battery
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Cite this Entry

“Booster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/booster. Accessed 11 Aug. 2026.

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Kids Definition

booster

noun
boost·​er ˈbü-stər How to pronounce booster (audio)
1
: one that boosts
2
: an enthusiastic supporter
3
: booster shot
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)
: booster shot
(2)
: booster dose
b
: synergist sense 1
a chemical acting as a booster to sulfa drugs

More from Merriam-Webster on booster

Nglish: Translation of booster for Spanish Speakers

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