明矾石 míngfánshí alunite Definitions Defs Origin Strokes Stroke Words Sentences Sents 明矾 明礬 míngfán alum A colorless crystalline compound used as a water purifier, as a mordant in dyeing, and in leather tanning or paper manufacturing; also called 白矾 báifán or 明石 míngshí.石 shí noun stone rock; stone; (bound form) made of stone; rock-like