neptunian

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 ]