Mercury

/ˈmʌrkjəri/

/ˈmʌkjəri/

Other forms: Mercuries; Mercurys

In our solar system, Mercury is the smallest planet and the closest one to the Sun. It's named after the Roman god Mercury, the messenger of the gods.

Mercury is a small, rocky planet, barely larger than our moon and similarly covered in craters. On Mercury, days are long, but years are short — one day there, from noon to noon, is equal to about 176 Earth days, twice as long as Mercury's year: It only takes 88 Earth days for Mercury to orbit the Sun. This fast trip is why ancient Romans named it after their speedy messenger god. Because it's so close to the Sun, Mercury is only briefly visible from Earth just before sunrise or after sunset.

Definitions of Mercury

1. noun

   the smallest planet and the nearest to the sun
   example of:

   inferior planet

   any of the planets whose orbit lies inside the earth's orbit

   terrestrial planet

   a planet having a compact rocky surface like the Earth's; the four innermost planets in the solar system
2. noun

   (Roman mythology) messenger of Jupiter and god of commerce; counterpart of Greek Hermes
   example of:

   Roman deity

   a deity worshipped by the ancient Romans