Word Study
thalassic
CIDE DICTIONARY
thalassic, a. [Gr. qa`lassa the sea.].
Of or pertaining to the sea; -- sometimes applied to rocks formed from sediments deposited upon the sea bottom. [1913 Webster]
OXFORD DICTIONARY
thalassic, adj. of the sea or seas, esp. small or inland seas.
Etymology
F thalassique f. Gk thalassa sea
For further exploring for "thalassic" in Webster Dictionary Online