Definitions for "Block group"
(BG)–Combination of census blocks that is a subdivision of a census tract or block numbering area (BNA). A block group consists of all blocks whose numbers begin with the same digit in a given census tract or BNA; for example, BG 3 within a census tract or BNA includes all blocks numbered between 301 and 399. The BG is the lowest level of geography for which the Census Bureau has tabulated sample data in the 1990 census; it was used to tabulate sample data in the 1970 and 1980 censuses only for those areas that had block numbers.
a cluster of census blocks within a census tract
a cluster of census blocks within the same census tract
a geographic designation for areas that contain, according to the U