Coincident Descriptive of two or more features or boundaries that are physically in the same location; for example, a census tract boundary that also serves as a CCD boundary. Also, the common boundary of adjacent entities. See also adjacent, conjoint, contiguous.
Collection block For the 1990 census, a physical block, identified by a unique three-digit number, that was enumerated as a single geographic area regardless of any legal or statistical boundaries that passed through it. See also census block, collection geography, tabulation block, tabulation geography.
Collection geography The geographic entities used by the Census Bureau to take a census. In the 1980 census, this was district office/enumeration district/block; for 1990, district office/address register area/collection block.
Colony (American Indian) A type of American Indian reservation.
Commonwealth The legal designation for four States (Kentucky, Massachusetts, Pennsylvania, and Virginia) and two of the Outlying Areas (Puerto Rico and the Northern Mariana Islands). The Census Bureau does not use this term in presenting census data.
Community (American Indian) A type of American Indian reservation. See also American Indian subreservation area.
Compact disc—read-only memory (CD-ROM) A type of high-density optical or laser disc for use on small computers. One 4¾-inch CD-ROM can hold the contents of approximately 500 printed reports, 1,600 flexible diskettes, or 3 or 4 high-density computer tapes.
Comunidad A CDP in Puerto Rico for the 1990 census; formerly called an aldea. See also aldea, census designated place.
Congressional district (CD) An area established by State officials or the courts for the purpose of electing a person to the U.S. House of Representatives.
