If a computer is offline, it is not connected to the internet. Compare online.
[computing]
Offline is also an adverb.
Most software programs allow you to compose emails offline.
2. off line
offline in British English
(ˈɒfˌlaɪn) or off-line
adjective
1.
disconnected from a computer; switched off
2.
of, relating to, or concerned with a part of a computer system not connected to the central processing unit but controlled by a computer storage device
online
3.
extra to or not involving a continuous sequence of operations, such as a production line
4. radio, television
(of processes, such as editing) not carried out on the actual transmission medium
adverb
5.
while not connected to a computer or the internet
Examples of 'offline' in a sentence
offline
Going offline is easy but it harms progress.
The Sun (2016)
The money went on online and offline advertising used to make businesses and consumers aware of the scheme in Manchester and London.
Computing (2010)
She is now asking her followers to go offline for one week.
The Sun (2015)
The offline system was ideal for him.
Times, Sunday Times (2008)
We need to take our offline relationships online so that we stay in touch more often.
Christianity Today (2000)
Prices are the same online and offline.
Times, Sunday Times (2015)
Nor will we increase the online or offline dealing fees.
Times, Sunday Times (2014)
The past decade in technology is the story of how three companies shaped our online and offline lives.
Times, Sunday Times (2009)
Now its website has gone offline.
Times, Sunday Times (2016)
England need players to go offline.
Times, Sunday Times (2014)
Just compare online and offline businesses.
Times, Sunday Times (2006)
This allows the brain to go offline and pack away that day's information.
Times, Sunday Times (2013)
But for now it is a building site, where parts will go offline for a while.
Times, Sunday Times (2014)
In three years he has worked on many projects, both online and offline.
Times, Sunday Times (2013)
But at least our brains had time to grow normally, and we usually know when to come offline.
Times, Sunday Times (2015)
His computer is offline, but he was able to post letters to followers, asking them to publish them on their blogs.