Whitinsville, Massachusetts, United States [CDP]; population was 5,639 in 1990; housing units was 2,162 in 1990; location is 42°7'N 71°40'W; land area is 3.64 square miles (2,329 acres); water area is 0.41 square miles (262 acres); FIPS code is 79495 [SourceCBP]