alumina

[ uh-loo-muh-nuh ]

noun

1. the natural or synthetic oxide of aluminum, Al 2 O 3 , occurring in nature in a pure crystal form as corundum.

alumina

/ əˈluːmɪnə /

noun

1. another name for aluminium oxide

alumina

/ ə-lo̅o̅′mə-nə /

1. Any of several forms of aluminum oxide used in aluminum production and in abrasives, refractories, ceramics, and electrical insulation. Alumina occurs naturally as the mineral corundum and, with minor traces of chromium and cobalt, as the minerals ruby and sapphire, respectively. In its hydrated form it also occurs as the rock bauxite. Also called aluminum oxide. Chemical formula: Al 2 O 3 .

Word History and Origins

Origin of alumina¹

1780–90; < Latin alūmin-, stem of alūmen alum ¹ + -a ⁴

Word History and Origins

Origin of alumina¹

C18: from New Latin, plural of Latin alūmen alum

Example Sentences

Thanks to a A$400m federal loan, it is building one of the world’s largest alumina refineries near the coastal city of Gladstone, which it says will create hundreds of local jobs.

From BBC

The tiny particles they used were made of alumina, or sapphire, and are "very hard," Dowding says.

From Science Daily

The researchers tested a range of slags, made from demolition waste and added lime, alumina and silica.

From Science Daily

The activated alumina helps them get within the legal limit, but fluoride levels there are still far higher than most other communities in the U.S.

From Salon

Extracting the alumina leaves behind waste called red mud that is highly alkaline and can also contain toxic heavy metals such as cadmium.

From Science Magazine