from
The Collaborative International Dictionary of English v.0.48
Neptunian \Nep*tu"ni*an\, prop. a. [L. Neptunius belonging to
Neptune: cf. F. neptunien.]
1. Of or pertaining to the ocean or sea.
[1913 Webster]
2. (Geol.) Formed by water or aqueous solution; as, Neptunian
rocks.
[1913 Webster]
{Neptunian races} (Ethnol.), the Malay and Polynesian races.
{Neptunian theory} (Geol.), the theory of Werner, which
referred the formation of all rocks and strata to the
agency of water; -- opposed to the {Plutonic} theory.
[1913 Webster] Neptunian