遮断機【しゃだんき】
(railway) crossing gate, barrier (at a toll booth, parking lot, etc.)
遮断【しゃだん】
isolation, cut off, blockade, quarantine, interception, deprivation
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