Chillum, Maryland, United States [CDP]; population was 31,309 in 1990; housing units was 12,093 in 1990; location is 38°58'N 76°59'W; land area is 4.10 square miles (2,626 acres); water area is 0.02 square miles (13 acres); FIPS code is 16875 [SourceCBP]