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English definition of “back sb up”

back sb up

phrasal verb with back     /bæk/ verb
SUPPORT B2 to support or help someone: My family backed me up in my fight for compensation .Backing, supporting and defendingDefending and protecting
SAY IS TRUE to say that someone is telling the truth : Honestly , that's exactly what happened - Claire'll back me up.Proving and disproving
(Definition of back sb up from the Cambridge Learner's Dictionary © Cambridge University Press)

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