back sth up
back
adjective[ before noun ]
uk /bæk/us
 back pay/rent/tax, etc.
pay, rent, tax, etc. that should have been paid or was expected at an earlier time:
Most of the back taxes due were for the years 2006 through 2008.
 on the back burner
If something is on the back burner, it is not being dealt with at the present time, especially because it is not urgent or important, but it will be dealt with in the future:
Any plans of opening new restaurants are on the back burner until the recession ends.
I lost my job and had to put my plans to move house on the back burner.
 take a back seat
to become less important (than something else):
Agriculture, which generates only about $50 million a year in revenue, takes a back seat to other industries like oil and gas that bring in billions of dollars.
Environmental issues take a back seat in tough economic times.
to let other people have a more active and responsible position than you in an organization or activity:
After appointing a new chief executive, the chairman of the fashion chain is finally taking a back seat at the business he founded.
back
adverb
uk /bæk/us
in return or reply:
I'm busy at the moment - can I call you back?
I e-mailed the customer services department and they said they would get back to me tomorrow.

Examples of back

back
Members of both institutions operated in the same electoral context, facing the same voters in the same elections backed by the same political parties.
As a result of equilibrium play, the rivals can avoid fighting altogether by backing down or submitting to the other's demands at critical decision points.
Therefore, this prediction cannot be backed up and thus should only be treated as an upper limit.
The winds then backed to 190x after 1400 hours, but remained light throughout and exhibit the expected behaviour compared to the geostrophic flow above.
The diffusion pump is backed by a rotary mechanical pump of double stages.
The methodology is advantageous in that it provides an approach backed with theoretical foundations.
We need clear descriptions of circuit function and behaviour, backed up by recordings (and videos).
He was very sceptical about backing state funding for research in the area.
In what follows we hope to go some way in backing up that claim.
On the other hand, chapter six deals with the most frequent aetiologies backed by well-reviewed recent findings.
In this case, the gold certificates would be fully backed with gold by the monetary authority.
In addition, despite early set-backs, it appears that significant progress has been made in the acquisition of needed credit and business management skills.
The chamber is pumped by a diffusion pump backed by a rotary pump to a low pressure of around 1024 mbar through the diagnostic port.
I discuss below the financial incentives that backed this up.
However, he rapidly found himself backed into a corner.
See all examples of back
These examples are from corpora and from sources on the web. Any opinions in the examples do not represent the opinion of the Cambridge Dictionary editors or of Cambridge University Press or its licensors.

Collocations withback

back

These are words often used in combination with back.

Click on a collocation to see more examples of it.

arched back
A gentle kind of bucking with an arched back.
back beyond
The head is tilted slightly back, so that the eyes are turned upward toward the back beyond of space.
back brace
One miner, who had broken his back several months before, went down the stricken pit, with a back brace on, to rescue his fellow workers.
From
Wikipedia