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.
If the goal isn’t to replace jobs, frame it as a productivity booster, not a threat. Apurva Wadodkar, Forbes.com, 27 June 2025 Starship's upper stage has exploded and/or crashed into the sea on eight of its nine of its test flights to date (on two launches, the company managed to return the vehicle's Super Heavy booster to Starbase, where it was caught by the 'chopstick' arms on its launch tower). Brett Tingley, Space.com, 27 June 2025 The company plans to reuse the booster on a future mission. Matthew Glasser, ABC News, 25 June 2025 The first-stage booster flew for the 25th time, landing on the droneship A Shortfall of Gravitas. Richard Tribou, The Orlando Sentinel, 23 June 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 6 Jul. 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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