Long hill
Puʻu is a hill and loa is long. The name refers to the land rather than the water, and it is the older name for the whole estuary now called Pearl Harbor.
The lochs were famous for pearl oysters, which is where the English name came from, and for an enormous concentration of fishponds — the area supported one of the densest aquaculture systems in the Pacific. The oysters were largely gone by the late nineteenth century.
Kaʻahupāhau
The harbour is associated with Kaʻahupāhau, a shark guardian said to protect the people of the area from other sharks. She is among the best known of the shark ʻaumākua, and stories about her are still told.