アルミナアルミナFreq.FrequencyTop 100,000Meanings1nounalumina; aluminum oxideTechnical term for aluminum oxide (Al₂O₃), used in ceramics, abrasives, and as a catalyst support.アルミナは研けん磨ま剤ざいとして広ひろく使つかわれている。Alumina is widely used as an abrasive.