noun
reserve equipment; backup unit; spare
Refers to equipment kept in reserve for use when the primary equipment fails or is unavailable. Common in technical, industrial, and military contexts.
停電に備えて予備装置を用意しておく。
We keep backup equipment ready in case of a power outage.
この工場では、主要な機械が故障したとき
In this factory, reserve equipment is always stored in case the main machinery breaks down.
Compound of 予備 (yobi, 'reserve, spare') and 装置 (sōchi, 'equipment, device').