Interruption or suspension; a cessation of communication, traffic, or services.
台風の影響で鉄道が不通になった。
Rail service was suspended due to the typhoon.
山の土砂崩れで道路が不通になっている。
The road is blocked by a landslide in the mountains.
連絡が不通で、彼と数日間連絡が取れなかった。
Communication was cut off, and I couldn't reach him for several days.