Dictionary
mer•cu•ry
Pronunciation: (mûr'kyu-rē), [key]—
n.,
—pl. -ries.
1. Chem.a heavy, silver-white, highly toxic metallic element, the only one that is liquid at room temperature; quicksilver: used in barometers, thermometers, pesticides, pharmaceutical preparations, reflecting surfaces of mirrors, and dental fillings, in certain switches, lamps, and other electric apparatus, and as a laboratory catalyst.
Symbol: Hg;
at. wt.: 200.59;
at. no.: 80;
sp. gr.: 13.546 at 20°C;
freezing point: -38.9°C;
boiling point: 357°C.
2. Pharm.this metal as used in medicine, in the form of various organic and inorganic compounds, usually for skin infections.
3. (
cap.) the ancient Roman god who served as messenger of the gods and was also the god of commerce, thievery, eloquence, and science, identified with the Greek god Hermes.
4. (
cap.)
Astron.the planet nearest the sun, having a diameter of 3031 mi. (4878 km), a mean distance from the sun of 36 million mi. (57.9 million km), and a period of revolution of 87.96 days, and having no satellites: the smallest planet in the solar system. See table under
planet.
5. a messenger, esp. a carrier of news.
6. any plant belonging to the genus
Mercurialis, of the spurge family, esp. the poisonous, weedy
M. perennis of Europe.
7. Good-King-Henry.
8. (
cap.)
Aerospace.one of a series of U.S. spacecraft, carrying one astronaut, that achieved the first U.S. suborbital and orbital manned spaceflights.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
