mercury

noun mer·cu·ry \ˈmər-kyə-rē, -k(ə-)rē\

: a silver metal that is liquid at normal temperatures

: the mercury in a thermometer that shows the air's temperature

Mercury : the planet that is closest to the sun

plural mer·cu·ries

Full Definition of MERCURY

a capitalized : a Roman god of commerce, eloquence, travel, cunning, and theft who serves as messenger to the other gods — compare hermes

b often capitalized archaic : a bearer of messages or news or a conductor of travelers

[Middle English mercurie, from Medieval Latin mercurius, from Latin, the god]

a : a silver-white poisonous heavy metallic element that is liquid at ordinary temperatures and is used especially in batteries, in dental amalgam, and in scientific instruments —called also quicksilver — see element table

b : the column of mercury in a thermometer or barometer; also : temperature <the mercury rose above 70 degrees>

capitalized : the planet nearest the sun — see planet table

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Origin of MERCURY

Latin Mercurius, Roman god and the planet

First Known Use: 14th century

MERCURIES Defined for Kids

mercury

noun mer·cu·ry \ˈmər-kyə-rē\

Definition of MERCURY for Kids

: a heavy silvery white poisonous metallic chemical element that is liquid at ordinary temperatures

: the column of mercury in a thermometer or barometer

cap : the planet that is nearest the sun and has a diameter of about 3000 miles (4700 kilometers)

Medical Dictionary

mercury

noun mer·cu·ry \ˈmər-kyə-rē, -k(ə-)rē\

plural mer·cu·ries

Medical Definition of MERCURY

: a heavy silver-white poisonous metallic element that is liquid at ordinary temperatures and used especially in scientific instruments—symbol Hg; called also quicksilver; see element table

: a pharmaceutical preparation containing mercury or a compound of it

Biographical Note for MERCURY

Mercury, Roman mythological character. In Roman mythology Mercury became identified with the Greek god Hermes. This god was known especially as the fleet-footed messenger of the gods. He was also the god of science and the arts and the patron of travelers and athletes. He is typically represented in art as a young man wearing a winged helmet and winged sandals and bearing a caduceus. The metal mercury was named after him most probably because he symbolizes mobility.