With a hint of sunshine, mystique, and devotion about it, Sulwyn is a Welsh name associated with the Christian festival of Pentecost. It combines the elements of Dydd Sul (meaning Sunday) and gwyn (meaning white or holy), and translates literally to “white Sunday” – another name for Whitsun or Pentecost. 
 
It is also theorized that the name could simply combine Sul, meaning sun, with -wyn (meaning white and fair), to give the meaning ‘fair sun’. Nickname Sunny might then feel just right.
 
Welsh broadcaster Sulwyn Thomas is a notable bearer of this underused gem – one that hasn’t been used as a given name since the 70s! It is however still seen as a middle name, for babies of any gender.

Sulwyn

Sulwyn Origin and Meaning