重ねる
かさねる · kasaneru · JLPT N3 · verb-ichidan
to put something on another
🥞📚 重 = layered or heavy; kasa-neru: stack casa on casa, layer on layer
重 means heavy or layered, as in 重箱 (jūbako, stacked lunch boxes). Kasaneru sounds like casa + neru: putting one casa (house) on top of another. Its partner 重なる (kasanaru) means the pile builds up by itself.
重 — person 人 + east 東 (phonetic)
Originally depicted a person carrying a heavy bundle on their back, suggesting weight and burden. The 東-like element served as a phonetic component. Over time the character split into two readings: zhòng meaning 'heavy' and chóng meaning 'repeat/again'.