硬こう石せっけんMeaningsNoun1. hard soap; soda soapOther spellings硬こう石せっ鹸けん硬こう石せっ鹼けんUsage share unknownKanji used硬hard like a rock石stoneKanji in other spellings鹸lye鹼alkalineComposed of硬こうhardnessNoun石せっけんsoapNoun