noun
automatic calling unit; ACU
Computing term for a device that automatically places calls or pages.
このシステムは自動呼び出し装置を使って、緊急時に担当者を呼び出す。
This system uses an automatic calling unit to page the person in charge in an emergency.
Compound of 自動 (automatic) + 呼び出し (calling, paging) + 装置 (device, apparatus).