室～
しつ～ · shitsu～ · JLPT N2 · noun
room
🚪 室 = room: 教室 kyoushitsu = teaching room, 寝室 shinshitsu = sleeping room
室 is a suffix meaning room. Add it to the purpose of a room: 会議室 kaigishitsu is a meeting room, and 事務室 jimushitsu is an office.
室 — roof 宀 + arrive 至
A semantic compound: 宀 (roof/house) over 至 (to arrive). The image is a place one arrives at and stays in — an inner room. From 'inner chamber' the meaning broadened to 'room' generally, and by extension to specialized rooms like an office or laboratory.