A Mermanaut is an explorer of the aquatic realm. This exploration
may take the form of spiritual, physical, or mental exploration of the planets vast oceans, and the worlds, secrets, and treasures they contain.
The word is a compound of mere, mermaid/man, and naut.
Mere is the Old
English word for sea. With the addition of “ma” (merma) both genders of mermaid and merman are represented. Finally, the term "naut" is from nautes (
greek: ναύτης), meaning sailor.