The name Moana is a girl's name of Maori, Polynesian origin meaning "Sea". Moana and is often added to lists like Names That Mean Water and discussed in our forums with posts like "Adding Then Eliminating -- Girls Themed".
From the experts:
This Maori name, often heard in New Zealand, is an exotic, evocative choice for a sea lover. Moana is a Polynesian sea god and was also an alternate name for the heroine Ofelia in Pan's Labyrinth. Moana may also be a color name for a deep ocean blue ("lanu moana"). Don't be tempted to shorten this name to "Moa" ("chicken").