Tunis is the transcription of the Arabic name تونس which can be pronounced as "Tūnus", "Tūnas", or "Tūnis". All three variations were mentioned by the Greek-Syrian geographer al-Rumi Yaqout in his Mu'jam al-Bûldan (Dictionary of Countries).
Different explanations exist for the origin of the name Tunis. Some scholars relate it to the Phoenician goddess Tanith ('Tanit or Tanut), as many ancient cities were named after patron deities. Some scholars claim that it originated from Tynes, which was mentioned by Diodorus Siculus and Polybius in the course of descriptions of a location resembling present-day Al-Kasbah; Tunis's old Berber Bourgade.
Another possibility is that it was derived from the Berber verbal root ens which means "to lie down" or "to pass the night". Given the variations of the precise meaning over time and space, the term Tunis can possibly mean "camp at night", "camp", or "stop". There are also some mentions in ancient Roman sources of such names of nearby towns as Tuniza (currently El Kala), Thunusuda (currently Sidi-Meskin), Thinissut (currently Bir Bouregba), and Thunisa (currently Ras Jebel). As all of these Berber villages were situated on Roman roads, they undoubtedly served as rest-stations or stops.