Refers specifically to designated areas in China with special economic regulations. Often abbreviated as SEZ.
See also: 経済特別区
Shenzhen is one of China's first special economic zones.
特区 is the shorthand form typically seen in news reports, whereas 特別経済区 is the full official name for a Chinese special economic zone.
特別経済区 is the fuller, less ambiguous form of the same term that 特別区 can abbreviate for a special economic zone.
Compound of 特別 (special) + 経済 (economy) + 区 (zone). A direct translation of the English term 'special economic zone'.