Pronunciation: (nep'tOOn, -tyOOn),[key] —n. any whelk of the genus Neptunea, esp. N. decemcostata, common along the eastern coast of North America and having a shell with seven to ten raised reddish-brown spiral ridges on a pale beige or yellow background.
Pronunciation: (nep'tOOn, -tyOOn),[key] —n. 1. the ancient Roman god of the sea, identified with the Greek god Poseidon.
2. the sea or ocean: Neptune's mighty roar. 3. Astron.the planet eighth in order from the sun, having an equatorial diameter of 30,200 mi. (48,600 km), a mean distance from the sun of 2794.4 million mi. (4497.1 million km), a period of revolution of 164.81 years, and two moons. See table under planet (def. 1).
4. a township in E New Jersey. 28,366.