Definition

1. Noun:
   • A heavy, silvery, toxic metallic element that is liquid at room temperature: Mercury is a chemical element (symbol Hg) known for being the only metal that is liquid under standard conditions for temperature and pressure.
   • Temperature measured by a mercury thermometer: Used informally to refer to the temperature reading, as mercury was historically the liquid used in many thermometers.
   • (Mercury) The smallest and innermost planet in the Solar System: The planet closest to the Sun.
   • (Mercury) The Roman god of commerce, communication, and travel, messenger of the gods: In Roman mythology, the counterpart to the Greek god Hermes.

Examples of Usage

• Noun (Element):
  • The old thermometer contained mercury.
  • Mercury pollution is a serious environmental concern.
• Noun (Temperature):
  • The mercury dropped below freezing last night.
• Noun (Planet):
  • Mercury has a very thin atmosphere.
• Noun (Mythology):
  • Mercury was often depicted with winged sandals.

Advanced Usage

• "The mercury is rising": An idiom meaning the temperature is increasing; often used figuratively to indicate that a situation is becoming more intense or active.
  • With summer approaching, the mercury is rising.
  • Tensions in the region are high; the mercury is rising.
• "The mercury is falling": An idiom meaning the temperature is decreasing.
  • Bundle up; the mercury is falling fast.

Variants and Related Words

• Mercurial (adjective): Subject to sudden or unpredictable changes of mood or mind; lively, quick-witted. (Derived from the perceived qualities of the god Mercury and the mobility of liquid mercury).
  • She has a mercurial temperament.
• Mercuric (adjective): Relating to mercury with a valence of two.
  • Mercuric chloride is a compound.
• Mercurous (adjective): Relating to mercury with a valence of one.

Synonyms

• Quicksilver: Another name for the metallic element mercury, emphasizing its liquid, shiny appearance.
• Hydrargyrum: The Latin origin of the chemical symbol 'Hg'.

Related Phrases

• Mad as a hatter: A historical idiom related to mercury poisoning, as hat makers used mercury nitrate in felt production, which could cause neurological damage.
  • His erratic behavior made him seem mad as a hatter.

Related Idioms

• "To have mercury in one's veins": To be very energetic, quick, or restless. (A less common, figurative idiom).
  • The young athlete seems to have mercury in his veins.

Noun

1. temperature measured by a mercury thermometer
   • the mercury was falling rapidly
2. the smallest planet and the nearest to the sun
3. (Roman mythology) messenger of Jupiter and god of commerce; counterpart of Greek Hermes
4. a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures