緩かん降こう機きMeanings1nounslow-descent device; evacuation descenderTechnical term for a device used to evacuate tall buildings by controlled descent, often a rope-based system.高こう層そうビルには緩かん降こう機きの設せっ置ちが義ぎ務む付づけられている。High-rise buildings are required to have slow-descent devices installed.