Dundee ( (); Scots: Dundee Scottish Gaelic: Dùn Dè or Dùn Dèagh [ˈt̪uːn tʲeː]) is Scotland's fourth-largest city and the 51st-most-populous built-up area in the United Kingdom. The mid-year population estimate for 2018 was 148,750, giving Dundee a population density of 2,478/km2 or 6,420/sq mi, the second-highest in Scotland. It lies within the eastern central Lowlands on the north bank of the Firth of Tay, which feeds into the North Sea. Under the name of Dundee City (officially the City of Dundee), it forms one of the 32 council areas used for local government in Scotland.