Sea spray
ʻEhu is the reddish tinge of spray or of a person's hair, and kai is the sea. ʻEhukai is the fine mist thrown up where surf breaks — lit reddish by low sun.
The name is a good example of how precisely Hawaiian describes water. It is not foam, not surf, not spray in general, but specifically the airborne mist off breaking waves.
Pipeline
The reef offshore produces the wave known as the Banzai Pipeline, which breaks in shallow water over sharp coral and is among the most dangerous in the world. The name Pipeline dates from the early 1960s and is not Hawaiian.