Word Study
Tethys
CIDE DICTIONARY
Tethys, n. [NL., fr. Gr. an oyster, or a kind of ascidian.].
A genus of a large naked mollusks having a very large, broad, fringed cephalic disk, and branched dorsal gills. Some of the species become a foot long and are brilliantly colored. [1913 Webster]
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