封顶
fēng dǐng · HSK 7
to cap the roof
🏠🧢 封 (seal) + 顶 (top) = seal the top — roof it or cap it
封 means to seal or close off; 顶 means top or peak. Together: seal the top, i.e. finish a roof. Extends figuratively to capping anything at a maximum — spending, prizes, salaries.
封 — earth 土 doubled (圭) + inch 寸 (hand)
Originally a pictograph of a hand planting a sapling on a mound of earth, marking a boundary. From this came the meaning of granting fiefs to nobles, then sealing or closing off territory. The modern senses 'to seal' and 'envelope' both stem from this idea of enclosing.
顶 — 页 (head) + 丁 (phonetic)
顶 is a semantic-phonetic compound. The 页 component, originally a pictograph of a head, gives the meaning — the top of the head, hence 'top' or 'peak.' The 丁 component supplies the sound (dīng → dǐng). It later extended to verbs like 'support from below' or 'carry on the head.'