Hypertext Webster Gateway: "iridium"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Iridium \I*rid"i*um\, n. [NL., fr. L. iris, iridis, the rainbow.
So called from the iridescence of some of its solutions. See
{Iris}.] (Chem.)
A rare metallic element, of the same group as platinum, which
it much resembles, being silver-white, but harder, and
brittle, and indifferent to most corrosive agents. With the
exception of osmium, it is the heaviest substance known, its
specific gravity being 22.4. Symbol Ir. Atomic weight 192.5.
Note: Iridium usually occurs as a native alloy with osmium
(iridosmine or osmiridium), which may occur alone or
with platinum. Iridium, as an alloy with platinum, is
used in bushing the vents of heavy ordnance. It is also
used for the points of gold pens, and in a finely
powdered condition (iridium black), for painting
porcelain black.
From WordNet (r) 1.7 (wn)
iridium
n : a heavy brittle metallic element of the platinum group; used
in alloys; occurs in natural alloys with platinum or
osmium [syn: {Ir}, {atomic number 77}]
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.