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booster

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noun [countable] American English pronunciation: booster /ˈbustər/ 
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singularbooster
pluralboosters

Related dictionary definitions

  1. 2
    something that makes you feel more confident, more healthy, etc.

    Fruit is an excellent health booster.

    confidence/morale booster:

    A new haircut can be a great confidence booster.

  2. 4
    American someone who publicly supports a person, plan, or organization

    The new airport, say its boosters, would do a lot for the local economy.

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a method of financial trading in which share prices are hidden and not openly available to the public

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