mercury

[ mur-kyuh-ree ]

noun

, plural mer·cu·ries.

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. : Hg; : 200.59; : 80; : 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 3,031 miles (4,878 km), a mean distance from the sun of 36 million miles (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, especially a carrier of news.
6. any plant belonging to the genus Mercurialis, of the spurge family, especially 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.

Mercury

¹

/ ˈmɜːkjʊrɪ /

noun

1. Roman myth the messenger of the gods Greek counterpartHermes

mercury

²

/ ˈmɜːkjʊrɪ /

noun

1. Also calledquicksilverhydrargyrum a heavy silvery-white toxic liquid metallic element occurring principally in cinnabar: used in thermometers, barometers, mercury-vapour lamps, and dental amalgams. Symbol: Hg; atomic no: 80; atomic wt: 200.59; valency: 1 or 2; relative density: 13.546; melting pt: –38.842°C; boiling pt: 357°C
2. any plant of the euphorbiaceous genus Mercurialis See dog's mercury
3. archaic.
   a messenger or courier

Mercury

³

/ ˈmɜːkjʊrɪ /

noun

1. the second smallest planet and the nearest to the sun. Mean distance from sun: 57.9 million km; period of revolution around sun: 88 days; period of axial rotation: 59 days; diameter and mass: 38 and 5.4 per cent that of earth respectively

Mercury

¹

1. The planet closest to the Sun and the smallest in the solar system. Mercury is a terrestrial or inner planet , second in density only to Earth, with a rugged, heavily-cratered surface similar in appearance to Earth's Moon. Its rotational period of 58.6 days is two-thirds of its 88-day orbital period, thus, it makes three full axial rotations every two years. Mercury's atmosphere is almost nonexistent; this fact, which produces rapid radiational cooling on its dark side, together with its proximity to the Sun, gives it a temperature range greater than any other planet in the solar system, from 466° to −184°C (870° to −300°F). Because it is so close to the Sun, Mercury is only visible shortly before sunrise or after sunset, and observation is further hindered by the fact that its light must pass obliquely through the lower atmosphere where it is distorted or filtered by dust and pollution.
2. See Table at solar system

mercury

²

/ mûr′kyə-rē /

1. A silvery-white, dense, poisonous metallic element that is a liquid at room temperature and is used in thermometers, barometers, batteries, and pesticides. Atomic number 80; atomic weight 200.59; melting point −38.87°C; boiling point 356.58°C; specific gravity 13.546 (at 20°C); valence 1, 2.
2. See Periodic Table

mercury

¹

1. 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.

Mercury

²

1. 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 .)

Mercury

³

1. The Roman name of Hermes , the messenger of the Greek and Roman gods.

Notes

The term mercury is used figuratively in such expressions as “The mercury's rising” to mean that the temperature is going up.

Word History and Origins

Origin of mercury¹

1300–50; Middle English Mercurie < Medieval Latin, Latin Mercurius, akin to merx goods

Word History and Origins

Origin of mercury¹

C14: from Latin Mercurius messenger of Jupiter, god of commerce; related to merx merchandise

Word History

Like a few other elements, mercury has a chemical symbol, Hg, that bears no resemblance to its name. This is because Hg is an abbreviation of the Latin name of the element, which was hydrargium. This word in turn was taken over from Greek, where it literally meant “water-silver.” With this name the Greeks were referring to the fact that mercury is a silvery liquid at room temperature, rather than a solid like other metals. Similarly, an older English name for this element is quicksilver, which means “living silver,” referring to its ability to move like a living thing. (The word quick used to mean “alive,” as in the Biblical phrase “the quick and the dead.”) The name mercury refers to the fact that the element flows about quickly: the name comes from the Roman god Mercury, who was the swift-footed messenger of the gods.

Example Sentences

During the washing process, various chemicals, including mercury and cyanide, are used to help extract the gold from the soil, polluting big and small rivers.

From BBC

Some parts of England could even see the mercury touching 23 or 24C by Wednesday.

From BBC

When she was in middle school, Alaina Wood learned about an environmental disaster — a coal ash spill into the Emory River, west of Knoxville, Tenn., that released toxic sludge containing arsenic and mercury.

From Los Angeles Times

The mercury in downtown Los Angeles and the Long Beach Airport is predicted to reach 104 degrees and Los Angeles International Airport is expected to reach 93 degrees.

From Los Angeles Times

Prosecutors said the way the company mismanaged the waste led to harmful levels of carcinogenic chemicals, lead, arsenic and mercury being released into the air, soil and water.

From BBC

Related Words

• earth