1 definition found unalaska - U.S. Gazetteer (1990) : Unalaska, AK (city, FIPS 80770) Location: 53.93447 N, 166.51042 W Population (1990): 3089 (682 housing units) Area: 270.1 sq km (land), 288.5 sq km (water) Zip code(s): 99685