册
cè · HSK 5
book
📖 册 is a pictograph of bamboo slips bound by cord — an ancient book/volume
册 (cè) depicts vertical bamboo strips tied together with a horizontal cord, the original form of a book before paper. Today it's a measure word for bound volumes and the noun for a booklet or register.
册 — two bamboo strips 竹 bound by a cord
册 is a pictograph of ancient bamboo or wooden writing slips threaded together with a cord, the earliest form of a book in China. The original meaning was a bound bundle of slips, which broadened to mean a volume, register, or booklet. Modern uses like 书册 (book) and 注册 (to register) preserve this sense.