1 definition found marmaduke - U.S. Gazetteer (1990) : Marmaduke, AR (city, FIPS 44240) Location: 36.18835 N, 90.38778 W Population (1990): 1164 (520 housing units) Area: 2.7 sq km (land), 0.0 sq km (water) Zip code(s): 72443