Neptunian

[ nep-too-nee-uh n, -tyoo- ]
/ nɛpˈtu ni ən, -ˈtyu- /

adjective

pertaining to Neptune or the sea.
pertaining to the planet Neptune.
(often lowercase) Geology. formed by the action of water.

Origin of Neptunian

First recorded in 1650–60; Neptune + -ian

Related forms

trans-Nep·tu·ni·an, adjective
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Examples from the Web for neptunian

British Dictionary definitions for neptunian

Neptunian

/ (nɛpˈtjuːnɪən) /

adjective

of or relating to the Roman god Neptune or the sea
of, occurring on, or relating to the planet Neptune
geology (of sedimentary rock formations such as dykes) formed under water
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012