사무실
samusil · TOPIK 1
office
🏢 事務室 = matter (사) + duty (무) + room (실): the room for business duties
사무 (事務) means office work or clerical business, and 실 (室) is the room suffix found in 교실 (classroom) and 화장실 (restroom). So 사무실 is literally the work-business room.