alumina

noun

alu·​mi·​na ə-ˈlü-mə-nə 

: the oxide of aluminum Al₂O₃ that occurs both in pure form as corundum and in hydrated forms (as in bauxite)

Examples of alumina in a Sentence

Recent Examples on the Web

After the solution settles or is filtered, the aluminum minerals are harvested, forming a material known as alumina, and the rest of the materials form a solid waste known as red mud. —New Atlas, 17 Sep. 2025

The new centimeter-wide disks are made from two thin perforated membranes of ceramic alumina connected by tiny vertical supports. —Payal Dhar, Scientific American, 19 Aug. 2025

High purity alumina is another key material for AI technologies which also presents important opportunities for innovation in deriving the material from a range of existing material stocks. —Saleem H. Ali, Forbes.com, 21 July 2025

Scientists think that the quantity of alumina from incinerated satellites is already approaching the same levels that result from the atmospheric demise of natural space rocks such as asteroids or meteoroids, which contain only trace amounts of aluminum. —Tereza Pultarova, Space.com, 2 Feb. 2025

Word History

Etymology

New Latin, from Latin alumin-, alumen alum

First Known Use

circa 1790, in the meaning defined above

Rhymes for alumina

• lumina

Kids Definition

alumina

noun

alu·​mi·​na ə-ˈlü-mə-nə 

: the oxide of aluminum that occurs in nature as corundum and in bauxite and is used as a source of aluminum, as an abrasive, and as an absorbent

Medical Definition

alumina

noun

alu·​mi·​na ə-ˈlü-mə-nə 

: an oxide of aluminum Al₂O₃ that occurs native as corundum and in hydrated forms (as in bauxite) and is used in antacids

called also aluminum oxide