 Compare the Welsh "tyddyn".From Celtic *"ardu-" 'high' (Irish "ard")
From Brythonic *"abona" 'river' (Welsh "afon")
From Celtic *"iska" 'water' (Irish "uisce")
First element from Celtic *"briga" 'hill'
From Celtic *"brigant-" 'high, lofty, elevated' (or divine name, Brigantia)
Derived from Welsh "bryn", 'hill'.From *"kamulos" 'Camulus' (divine name) + Celtic *"dūnon" 'fortress'
First element from Brythonic *"crüg" 'hill' (Irish "cruach")
From tribal name "Dumnonii" or "Dumnones", from Celtic *"dumno-" 'deep', 'world'
From Celtic *"dubr-" 'water', *"dubrās" 'waters' (Welsh "dwfr"; Breton "dour")
First element is possibly "dun", ' hill fort' (Welsh ddin, 'fort').