From The Collaborative International Dictionary of English v.0.44 [gcide]:
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.
From WordNet (r) 2.0 [wn]:
Define.com is a registered nonprofit corporation dedicated solely to the global public interest and the advancement of humanity. It belongs to all of us who have a desire to promote electronic democracy, science, creativity, imagination, reason, critical thinking, peace, race and gender equality, civil rights, equal access to education, personal liberty, free speech, animal rights, compassionate and nonviolent parenting, social and economic justice, global monetary reform, Secular Humanism, cognitive liberty and a permanent cessation of The War on Drugs.
Let's see what we can do if we put our heads together.0