Aba, city (1991 est. pop. 264,000), SE Nigeria. It is an important regional market, a road and rail hub, and a manufacturing center for cement, textiles, pharmaceuticals, processed palm oil, shoes, plastics, soap, and beer. Originally a small market town, Aba was developed by the British as an administrative center in the early 20th cent. In 1929, women in Aba rioted against Britain's arbitrary use of indigenous persons as rulers and against direct taxation.