The definition of CCTV refers to closed-circuit television, or the use of video cameras to transmit images to a specific limited number of televisions on the same network or circuit.(noun)
When a security system allows you to monitor what is going on in a home on a monitor on your desk, this is an example of CCTV.
See CCTV in Webster's New World College Dictionary
See CCTV in American Heritage Dictionary 4
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