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 flight will carry 36 Amazon Leo satellites aboard an Ariane 64, the rocket’s four-booster configuration. — Eric Berger, ArsTechnica, 23 Oct. 2026 The booster, meanwhile, reoriented for its descent back to Earth. — Josh Dinner, Space.com, 23 Oct. 2026 Starship is a two-part launch system that includes the Super Heavy rocket booster and the upper Starship spacecraft, a 171-foot-tall vehicle packed with six rocket engines of its own. — Jackie Wattles, CNN Money, 23 Oct. 2026 Industry observers have also long argued that the closure works as a counterintuitive sales booster, because the scarcity has become part of the brand and helps drive traffic on the other six days. — Heather Occhino, Fortune, 22 Oct. 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 27 Oct. 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
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