city, northeastern Tamil Nadu (Tamil Nādu) state, southeastern India, on the Bay of Bengal coast. Its name is derived from kuttal-ur (“junction town”) and refers to its location near the junction of the Ponnaiyar River with its tributary, the Gadilam River. Both rivers frequently flood, causing damage to the city.

An ancient seaport, Cuddalore developed rapidly after trading rights were obtained by the British East India Company in 1682, but it later declined with the expansion of Madras ( Chennai). It now handles only a small percentage of Tamil Nadu's foreign trade, dealing almost exclusively with Malaysia and Singapore. Its fishing and shipbuilding industries have been expanding. Cuddalore has several colleges affiliated with the University of Madras. It is the site of the 7th-century Pataleswarar Temple to the Hindu god Shiva. Pop. (2001) 158,634.