'Thalassic' definitions:

Definition of 'thalassic'

From: WordNet
adjective
Relating to the seas, especially smaller or inland seas; "deposits of sediment in gulfs and seas rather than in the ocean proper are known as thalassic deposits"- Scientific American

Definition of 'Thalassic'

From: GCIDE
  • Thalassic \Tha*las"sic\, a. [Gr. qa`lassa the sea.] (Geol.) Of or pertaining to the sea; -- sometimes applied to rocks formed from sediments deposited upon the sea bottom. [1913 Webster]