Wahiawā is a census-esignated place (CDP) and in the center of Oʻahu Island in the Wahiawa District of Honolulu County, Hawaii, United States, on the plateau or "central valley" between the two volcanic mountains that comprise the island. In Hawaiian, wahi a wā means "place of noise", perhaps a reference to the fact that once upon a time, heavy surf on the distant coast could be heard here. The population was 16,151 at the 2000 census.