Hypertext Webster Gateway: "Corundum"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Corundum \Co*run"dum\ (k?-r?n"d?m), n.; pl. {Corundums} (-d?mz).
[Also corindon.] [From Hind. kurand corundum stone.] (Min.)
The earth alumina, as found native in a crystalline state,
including sapphire, which is the fine blue variety; the
oriental ruby, or red sapphire; the oriental amethyst, or
purple sapphire; and adamantine spar, the hair-brown variety.
It is the hardest substance found native, next to the
diamond.
Note: The name corundum is sometimes restricted to the
non-transparent or coarser kinds. Emery is a
dark-colored granular variety, usually admixed with
magnetic iron ore.
From WordNet (r) 1.7 (wn)
corundum
n : very hard mineral used as an abrasive [syn: {corundom}]
Additional Hypertext Webster Gateway Lookup
Gateway by dict@stokkie.net
stock only wrote the gateway and does not have any control over the contents;
see the Webster Gateway FAQ,
and also the Back-end/database links and credits.