/ˈnɛptjuːn/ (NEP-tew-n)

Definitions

1. noun

the eighth and farthest planet from the sun in our solar system

“The discovery of Neptune was a groundbreaking moment in astronomical history.”

2. proper noun

the Roman god of the sea, equivalent to the Greek god Poseidon

“In Roman mythology, Neptune was often depicted with a trident.”

3. proper noun

a chemical element with the symbol Np and atomic number 93

“Neptune is a radioactive metallic element.”

4. adjective

relating to or characteristic of Neptune or the planet

“The neptunian moons are some of the most distant in our solar system.”