Neptune

/ˌnɛpˈtun/

/ˈnɛptun/

Other forms: Neptunes

In our solar system, Neptune is the planet that's farthest away from the sun. It takes 165 Earth years for Neptune to orbit the sun once.

Because of all the methane in its atmosphere, Neptune appears blue when viewed through powerful telescopes. This stormy blue surface influenced the eighth planet's name, which is inspired by the Roman god of the sea. Neptune has a root meaning "cloud." The ice giant became the most distant planet in the Milky Way when Pluto was reclassified as a lesser "dwarf planet" in 2006.

Definitions of Neptune

1. noun

   a giant planet with a ring of ice particles; the 8th planet from the sun is the most remote of the gas giants
   “the existence of Neptune was predicted from perturbations in the orbit of Uranus and it was then identified in 1846”

   example of:

   Jovian planet, gas giant

   any of the four outermost planets in the solar system; much larger than Earth and gaseous in nature (like Jupiter)

   outer planet

   (astronomy) a major planet whose orbit is outside the asteroid belt (Jupiter, Saturn, Uranus, Neptune, Pluto)

   superior planet

   any of the planets whose orbit lies outside the earth's orbit
2. noun

   (Roman mythology) god of the sea; counterpart of Greek Poseidon
   example of:

   Roman deity

   a deity worshipped by the ancient Romans