sign off
Pronunciation:
noun
Definitions
The closing of a radio or television station's studios and cessation of the broadcasting signal, usually overnight.
Example: Sign off for the small-town radio station was at midnight.
verb
Definitions
To log off; to stop using a computer, radio, etc., especially to stop talking.
Example: He finished the conversation and signed off.
To cease broadcasting a radio or television signal, usually at the end of a broadcasting day.
Example: Before he signed off the radio station for the night, the disc jockey played the National Anthem.
(followed by “on”) to give one's official approval to something for which it is needed
Example: Once the vice-president signs off on the project, we can start construction.