Neptune

Nep·tune  (nptn, -tyn)

n.

1.

a. Roman Mythology The god of water, later identified with the Greek Poseidon.

b. The sea.

2. The eighth planet from the sun, having a sidereal period of revolution around the sun of 164.8 years at a mean distance of 4.5 billion kilometers (2.8 billion miles), a mean radius of 24,000 kilometers (15,000 miles), and a mass 17.2 times that of Earth.

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[Latin Neptnus.]

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Nep·tuni·an (-tn-n, -ty-) adj.

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Neptune

Noun

1. the Roman god of the sea

2. the eighth planet from the sun

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Neptune  (nptn)

The eighth planet from the Sun and the fourth largest, with a diameter almost four times that of Earth. Neptune is a gas giant with a very active weather system, exhibiting extremely long and powerful storms with the fastest winds observed in the solar system. Neptune's axis is tilted 28.8° from the plane of its orbit, and its summer and winter seasons each last 40 years. For a period of 20 years out of every 248, Pluto's highly elliptical orbit crosses within that of Neptune, making Neptune the farthest planet from the Sun during that period. Neptune has four faint rings and 13 known moons and appears blue due to the absorption of red light by the methane within its atmosphere. See Table at solar system.

Thesaurus

Noun	1.	Neptune - (Roman mythology) god of the sea; counterpart of Greek Poseidon Roman mythology - the mythology of the ancient Romans
	2.	Neptune - 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" solar system - the sun with the celestial bodies that revolve around it in its gravitational field