蒸溜
じょうりゅう · jouryuu · JLPT N1 · noun
distillation
🧪 蒸 = steam + 溜 = collect in a pool: boil to steam, then collect the drops
This is the older spelling of 蒸留, which uses 留 (stay) in modern Japanese. Both mean vapor is cooled and the purified liquid is collected.
蒸 — grass 艹 + 丞 (phonetic) + fire 灬
Originally depicted plant stalks (艹) being heated over fire (灬), with 丞 providing the sound. The character first meant rising steam from burning hemp stalks used as torches, then broadened to mean steaming food or vapor rising. Modern uses extend metaphorically to 'flourishing' or 'thriving.'
溜 — water 氵 + 留 (liú, stay)
A semantic-phonetic compound: the water radical 氵 gives the meaning (smooth, slippery, flowing) while 留 supplies the sound. Originally describing water flowing swiftly and smoothly, it extended to mean 'slip,' 'glide,' or 'sneak away,' as well as 'slippery' surfaces.