石鹸
せっけん · sekken · JLPT N5 · noun
soap
🧼 石鹸 = stone + lye: soap was once a hard alkaline block
石 (seki) means stone and 鹸 (ken) means lye or alkali, so the word names a solid cake of alkali. Sound hook: sekken is close to second — soap is the second thing you reach for after water.