The name Thalassa is a girl's name of Greek origin meaning "the sea". Thalassa and is often added to lists like Badass Princess Names and discussed in our forums with posts like "Mother's Day "Lots-O-Girls" 5 Choices CAF".
From the experts:
A pretty, rarely used Greek name, Thalassa is the ancient personification of the sea, particularly the Mediterranean, who is sometimes considered the mother of Aphrodite.
In 1991, a newly discovered moon of Neptune was dubbed Thalassa.
This name would make a highly original, yet accessible and delicate choice.