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

Examples of MERCURY

  1. In the summer, the mercury can reach over 100 degrees Fahrenheit.

Origin of MERCURY

Latin Mercurius, Roman god and the planet
First Known Use: 14th century
MERCURY Defined for Kids


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


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.
July 28, 2015
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