TSUMUGU · B1 · 字
蒸
蒸 ＝ 艸 ＋ 烝
ㄓㄥ · zhēng
verb — to steam (food); for vapour to rise, evaporate
字源 FORM — what the parts do
艸義plants, stalks
烝聲zhēng — gives the sounda fire (灬) underneath heating water up
Plants (艸) over 烝 zhēng, the sound — and 烝 hides a fire (灬) at its foot, steam driven up off the heat. From the rising vapour: 蒸氣、蒸發、蒸饅頭. The 艸 on top recalls the steamed hemp-stalk the old graph named.
故事 STORY — a scene to remember it by
鍋底火（灬）一旺，白汽從草稈（艸）間直直竄上來——蒸。
The fire (灬) flares under the pot, white vapour shooting straight up through the stalks (艸) — steaming.
字源記憶法
意 · Meanings
(本義)蒸麻稈— hemp stalks dried over heat
→蒸氣、蒸發— to steam; vapour rising常用
⇒蒸煮、蒸饅頭— to cook by steam
(本義) original meaning · → ⇒ each arrow = one more step of extension
關 · Related
烝zhēngthe bare phonetic — 蒸 grows above; 烝 keeps the fire 灬 below丞chéngthe neighbour — 丞 reads chéng, 蒸 reads zhēng