alum
A chemical compound used in water purification, pickling, and as an astringent. In everyday contexts, it may appear in discussions of food additives or traditional remedies.
Alum is used for water purification.
Adding alum to eggplant pickles makes the color bright.
pickeringite
chrome alum
Katakana spelling is common for this chemical term; usually written in kana.
Kanji form is rare and technical; learners will mostly encounter the kana spellings.
The Japanese word みょうばん is a borrowing from Chinese 明礬 (míngfán), meaning 'alum'. The kanji 明 (bright) and 礬 (alum) reflect the compound's appearance and use.