楼梯
lóutī · HSK 4
stairs
🪜 楼 (building/floor) + 梯 (ladder) = floor-ladder = staircase
楼 means a multi-storey building or floor level; 梯 is a ladder or stepped device (also in 梯子 ladder, 滑梯 slide). Together: the ladder that connects floors — a staircase.
楼 — wood radical 木 + 婁 (lóu, phonetic)
楼 is a phono-semantic compound. The 木 radical signals wood, fitting a multi-storied wooden building, while 婁 supplies the lóu sound. Originally written 樓, it referred to a tower or upper story, and today means a multi-floor building or a specific floor.