The word Mannargudi is derived from the Tamil word Mannar referring to Vishnu and gudi referring to a place, meaning the Place of Vishnu. The town was also called Mannarkovil or Rajamannarkoil after the Rajagopalaswamy temple. The town is locally referred as Mannai. Hindus refer the place as Dakshina Dwarka, meaning Southern Dwarka. The town was known during the period of Nayaks for the tall compound wall around the Rajagopalaswamy temple, leading to the adage Mannargudi Mathil Azhagu, (meaning the walls of Mannargudi are beautiful). The town is also called Koil mattrum Madil Nagaram referring to the compound wall around the temple.