what does "off the air" mean?

China
February 10, 2007 2:18am CST
I can't find it in the dictionary
4 responses
@yueliu (1623)
• China
10 Feb 07
u copy this from me???!!!
• China
10 Feb 07
~~~HeiHei~~~ No the all, I really dont't konw what it means
• United States
11 Feb 07
It means not brodcasting at this time.
@yueliu (1623)
• China
10 Feb 07
I guess it means stop~~ eg channel 5 is off the air,which means we don't broadcast channel 5.Am I right?
• United States
10 Feb 07
I thought it was a figure of speech that meant a radio station was not broadcasting over the airwaves for a period of time.