遮断【しゃだん】
isolation, cut off, blockade, quarantine, interception, deprivation
遮断機【しゃだんき】
(railway) crossing gate, barrier (at a toll booth, parking lot, etc.)
遮断器【しゃだんき】
circuit breaker
遮る【さえぎる】
to interrupt, to obstruct (a view, someone's way, etc.), to block (light, wind, etc.), to intercept, to cut off