alundum vs aluminum oxide

alundum and aluminum oxide both are nouns.

Word	Noun	Adjective	Verb	Adverb
alundum	Yes	No	No	No
aluminum oxide	Yes	No	No	No

As nouns, aluminum oxide is a hypernym of alundum; that is, aluminum oxide is a word with a broader meaning than alundum:

alundum: a substance made of fused alumina
aluminum oxide: any of various forms of aluminum oxide occurring naturally as corundum

Other hypernyms of alundum include alumina, aluminium oxide.

alundum (noun)	aluminum oxide (noun)
a substance made of fused alumina	any of various forms of aluminum oxide occurring naturally as corundum