1 definition found grasonville - U.S. Gazetteer (1990) : Grasonville, MD (CDP, FIPS 34550) Location: 38.95798 N, 76.19423 W Population (1990): 2439 (1102 housing units) Area: 15.8 sq km (land), 0.1 sq km (water) Zip code(s): 21638