Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “back sth up”

back sth up

verb uk phrasal verb with back   /bæk/ us  
C2 to prove something is true: His claims are backed up by recent research. B2 to make an extra copy of computer information: Make sure you back up your files.
See also
(Definition of back sth up phrasal verb, verb from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of back sth up?
Add Cambridge dictionaries to your browser to your website

Definitions of “back sth up” in other dictionaries

Word of the Day

hello stranger

said to a person that you know but have not seen for a long time

Word of the Day

Come on – you can do it! Phrasal verbs with ‘come’.

by Liz Walter​,
November 19, 2014
As part of an occasional series on the tricky subject of phrasal verbs, this blog looks at ones formed with the verb ‘come’. If you are reading this blog, I’m sure you already know come from, as it is one of the first things you learn in class: I come from Scotland/Spain.

Read More 

silver splicer noun

November 17, 2014
informal a person who marries in later life Newly retired and now newlywed – rise of the ‘silver splicers’ Reaching pension age becomes a trigger to tie the knot as baby-boomers begin to redefine retirement

Read More