The dictionary that controls the process of compression and decompression. In DB2 for z/OS, this dictionary is created from the data in a table space or table space partition. In DB2 Database for Linux, UNIX, and Windows, the dictionary is created from the data in each table partition or each table in a database partition. A compression dictionary is specific to the table space, table space partition, or table from which it was created. See also automatic dictionary creation.