Lochearn, Maryland, United States [CDP]; population was 25,240 in 1990; housing units was 9,905 in 1990; location is 39°21'N 76°44'W; land area is 5.57 square miles (3,565 acres); water area is 0.02 square miles (13 acres); FIPS code is 47450 [SourceCBP]