Found 2 items, similar to alumina.
English → English (WordNet)
Definition: alumina
alumina
n : any of various forms of aluminum oxide occurring naturally
as corundum [syn:
aluminum oxide,
aluminium oxide]
English → English (gcide)
Definition: Alumina
Alumina
\A*lu"mi*na\, n. [L. alumen, aluminis. See
Alum.]
(Chem.)
One of the earths, consisting of two parts of aluminium and
three of oxygen,
Al2O3.
[1913 Webster]
Note: It is the oxide of the metal aluminium, the base of
aluminous salts, a constituent of a large part of the
earthy siliceous minerals, as the feldspars, micas,
scapolites, etc., and the characterizing ingredient of
common clay, in which it exists as an impure silicate
with water, resulting from the decomposition of other
aluminous minerals. In its natural state, it is the
mineral corundum.
[1913 Webster]