[mur-kyuh-ree] 
| 1. | Chemistry. 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; atomic weight: 200.59; atomic number: 80; specific gravity: 13.546 at 20°C; freezing point: −38.9°C; boiling point: 357°C. |
| 2. | Pharmacology. this metal as used in medicine, in the form of various organic and inorganic compounds, usually for skin infections. |
| 3. | (initial capital letter ) 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. | (initial capital letter) Astronomy. 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. |
| 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. | (initial capital letter) Aerospace. one of a series of U.S. spacecraft, carrying one astronaut, that achieved the first U.S. suborbital and orbital manned spaceflights. |
[good-king-hen-ree] | a European, chenopodiaceous weed, Chenopodium bonus-henricus, naturalized in North America, having spinachlike leaves. |
| mer·cu·ry (mûr'kyə-rē) n.
[Middle English mercurie, from Medieval Latin mercurius, from Latin Mercurius, Mercury.] |
| Mer·cu·ry (mûr'kyə-rē) n.
[Middle English Mercurie, from Old French, from Latin Mercurius.] |
In astronomy, the planet closest to the sun, named after the fleet-footed messenger of the Roman gods (see under “Mythology and Folklore”) because of its swift movement in its orbit. Mercury takes only eighty-eight days to go around the sun. (See solar system.)
Note: Mercury is sometimes visible from the Earth as a morning or evening star.
In chemistry, a heavy, silvery metallic element, a liquid at normal temperatures. Mercury expands or contracts rapidly in response to changes in temperature and therefore was once widely used in thermometers.
Note: The term mercury is used figuratively in such expressions as “The mercury's rising” to mean that the temperature is going up.
mercury mer·cu·ry (mûr'kyə-rē)
n.
Symbol Hg
A silvery-white poisonous metallic element, liquid at room temperature and used in thermometers. Atomic number 80; atomic weight 200.59; melting point -38.83°C; boiling point 356.73°C; specific gravity 13.546 (at 20°C); valence 1, 2. Also called hydrargyrum.
