mercury

(mûrˈkyə-rē)

1. Symbol Hg A silvery-white poisonous metallic element, liquid at room temperature and used in thermometers, barometers, vapor lamps, and batteries and in the preparation of chemical 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. Also called quicksilver. See Table at element.
2. Temperature: The mercury had fallen rapidly by morning.
3. Any of several weedy plants of the genera Mercurialis or Acalypha.

(mûrˈkyə-rē)

1. Roman Mythology A god that served as messenger to the other gods and was himself the god of commerce, travel, and thievery.
2. The smallest of the inner planets and the one nearest the sun, having a sidereal period of revolution about the sun of 87.97 days at a mean distance of 57.91 million kilometers (35.98 million miles) and a mean radius of approximately 2,440 kilometers (1,516 miles).