Where does “Tānītini” come from?

Tānītini (Rarotongan) comes from English Dunedin, from Scottish Gaelic Dùn Èideann, from Old Welsh Din Eidyn, from Old Welsh din, from Proto-Brythonic *din, from Proto-Celtic dūnom, from Proto-Indo-European dʰewh₂- — smoke; mist, haze.

Ancestry of “Tānītini”, step by step

Step	Language	Word	Meaning
1	English	Dunedin	An anglicisation of the Gaelic name for Edinburgh
2	Scottish Gaelic	Dùn Èideann	Edinburgh
3	Old Welsh	Din Eidyn	Edinburgh
4	Old Welsh	din	—
5	Proto-Brythonic	*din	a hill, fortified hill, fort
6	Proto-Celtic	dūnom	stronghold, rampart
7	Proto-Indo-European	dʰewh₂-	smoke; mist, haze

Every word from Proto-Indo-European dʰewh₂- →Every word from Proto-Celtic dūnom →Every word from Proto-Brythonic *din →