矾石 fánshí alunite Origin Definitions Defs Strokes Stroke Words Sentences Sents 矾 礬 fán alum Any of a group of hydrated double sulfate salts of certain metals, such as 明矾 míngfán, which are used in leather tanning, papermaking, and dyeing石 shí noun stone rock; stone; (bound form) made of stone; rock-like