Meaning : A person who backs a politician or a team etc..
Example :
All their supporters came out for the game.
They are friends of the library.
Synonyms : admirer, champion, friend, protagonist, supporter
Meaning : A thief who steals goods that are in a store.
Synonyms : lifter, shoplifter
Meaning : An amplifier for restoring the strength of a transmitted signal.
Synonyms : booster amplifier, booster station, relay link, relay station, relay transmitter
Meaning : The first stage of a multistage rocket.
Synonyms : booster rocket, booster unit, takeoff booster, takeoff rocket
Meaning : An additional dose that makes sure the first dose was effective.
Synonyms : booster dose, booster shot, recall dose