1 definition found waukesha - U.S. Gazetteer (1990) : Waukesha, WI (city, FIPS 84250) Location: 43.01247 N, 88.23821 W Population (1990): 56958 (22065 housing units) Area: 44.8 sq km (land), 0.1 sq km (water) Zip code(s): 53186, 53188