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English definition of “booster”

booster

noun [C]  /ˈbu·stər/ us  

booster noun [C] (SUPP0RTER)

an action or thing that improves or increases something: Winning this game was a great morale booster for the team. A booster is also someone who is an enthusiastic supporter of something.

booster noun [C] (ROCKET)

the first stage of a rocket (= object sent into space) that pushes it off the ground
(Definition of booster from the Cambridge Academic Content Dictionary © Cambridge University Press)
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