booster

noun

boost·​er ˈbü-stər 

: 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

• advocate
• advocator
• apostle
• backer
• champion
• espouser
• exponent
• expounder
• friend
• gospeler
• gospeller
• herald
• hierophant
• high priest
• paladin
• promoter
• proponent
• protagonist
• supporter
• true believer
• tub-thumper
• white knight

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

But one of the pivotal accomplishments this year for SpaceX came Oct. 13 when the rocket booster was able to steer autonomously back to the landing pad, where it was caught with two giant mechanical arms. —Eric Lagatta, USA TODAY, 15 Dec. 2024

The attempt was aborted four minutes into the test flight for unspecified reasons, and the booster subsequently landed in the Gulf of Mexico. —Michael D. Carroll, Newsweek, 13 Dec. 2024

Body care, hand soaps, candles, wallflowers fragrance refills, fragrance boosters, laundry detergent, hanging fragrance diffusers, and hand sanitizers are all on sale at Bath & Body Works right this second. —Katie Decker-Jacoby, StyleCaster, 13 Dec. 2024

And for years, boosters have struggled to offer up a satisfactory answer. —Charlie Warzel, The Atlantic, 11 Dec. 2024

Word History

First Known Use

1888, in the meaning defined above

Phrases Containing booster

• booster cushion
• booster dose
• booster seat
• booster shot

Kids Definition

booster

noun

boost·​er ˈbü-stər 

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 

: 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