The act of blocking or cutting off something physically or functionally — e.g., cutting power, blocking communication, or using a barrier to stop passage.
安全のために電源を遮断してから作業を行ってください。
For safety, please cut off the power before starting work.
線路に遮断機が下りているので踏切を渡れない。
The railroad crossing gates are down, so you can't cross the tracks.
台風で通信が遮断され、連絡が取れなくなった地域がある。
There are areas where communications were cut off by the typhoon and contact couldn't be made.