A "Hawaiian hotspot" refers to a volcanic region in the central Pacific Ocean where magma from deep within the Earth rises to create islands. This geological phenomenon is responsible for the formation of the Hawaiian Islands, which are a chain of volcanic islands that have emerged over millions of years as the Pacific tectonic plate moves over the hotspot. The hotspot is believed to be stationary, while the tectonic plate shifts, leading to the creation of new islands and the gradual erosion of older ones. As a result, the Big Island of Hawaii is the youngest and most active, while Kauai is one of the oldest islands in the chain.