Ambattur, city in southern India, in northeastern Tamil Nadu state, and within the Coromandel Coast along the Bay of Bengal. Located just west of Chennai (formerly known as Madras), Ambattur is one of the city's chief suburbs. Although many residents commute to jobs in Chennai, others work in Ambattur's growing industrial sector. A rail line and a national highway connect Ambattur with the center of Chennai. Extensive industrial and residential development in Ambattur in the southern part of the city, has encouraged rapid population growth. Population (1991) 215,424.