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English definition of “booster”

booster

noun
 
 
/ˈbuːstər/
a confidence/morale, etc booster something that makes you feel happier or more confidentEncouraging and urging onInspiration and inspiring
[C] an engine on a spacecraft that gives extra power for the first part of a flightSpace travel
(Definition of booster from the Cambridge Learners Dictionary © Cambridge University Press)
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