The elongated planetoid of Haumea is named for a Hawai'ian goddess with many children, and the two known moons of that planetoid are named for two of the goddess' many children. These two daughters of Haumea were indeed seen as goddesses in their own right, and Namaka (properly accented Nāmaka)* was seen as a goddess of the sea and maker of land.
Evidence suggests that Haumea's moons were formed in a violent impact event that shattered Haumea into pieces. Many of these pieces were scattered into the wider Kuiper Belt, but Haumea's gravity retained at least two as small moons: Hi'iaka the larger and Namaka very much the smaller.
Measurements of these small moons are difficult to make with certainty, but Namaka appears to be less than 200 km in diameter, about a half that of Hi'iaka, and it possesses only about a tenth of the mass of its fellow moon. This means that Namaka's orbit is highly influenced by its more massive outer companion, and while Hi'iaka follows an orbital path that is close to circular, Namaka's inner orbit is far less regular. Its path around Haumea has been tugged and stretched by the outer moon Hi'iaka so that it is distinctly eccentric in form, forming an elongated ellipse.
Haumea is a rocky body, lacking the icy mantle common to many Kuiper Belt objects, which was apparently lost in the same collision that created its moons. As debris from that collision, recaptured by Haumea's gravity, Namaka and its fellow moon Hi'iaka show a similar rocky composition with little of the surface ice found on similar objects.
* It is generally the case that names commonly spelt with accented characters in their original language lose those accents when they are applied to astronomical objects, simply for ease of reference. So, for example, the mythical Greek queen Pasiphaë (with a diaeresis mark on the final 'e') gave her name to the Jovian moon Pasiphae (without the accent mark). In the particular case of Namaka, the Hawai'ian goddess whose name is typically spelt Nāmaka gave her name to the moon in unaccented form.