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English definition of “back sth up”

back sth up

phrasal verb with back     /bæk/ verb
PROVE to prove that something is true : [often passive] His claims are backed up by recent research .Backing, supporting and defendingDefending and protecting
COMPUTER B2 to make an extra copy of computer information Computer concepts
(Definition of back sth up from the Cambridge Learner's Dictionary © Cambridge University Press)

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