Some references also say it was derived from a Prakrit dialect called Dhaka Bhasa; or Dhakka, used in the Rajtarangini for a watch-station; or it is the same as Davaka, mentioned in the Allahabad pillar inscription of Samudragupta as an eastern frontier kingdom. According to Rajatarangini written by a Kashmiri Brahman, Kalhana, the region was originally known as ''Dhakka''. The word ''Dhakka'' means ''watchtower''. Bikrampur and Sonargaon—the earlier strongholds of Bengal rulers were situated nearby. So Dhaka was most likely used as the watchtower for the fortification purpose.