Endellion: Civil parish and hamlet in northern Cornwall. Cornish form of Endelienta.

Endelienta: Latinized form of an unknown Celtic name, possibly Welsh Cenheidlon or Cynheiddon. This was the name of a 5th- or 6th-century Cornish saint whose birth name is lost. According to tradition she was a Welsh princess, daughter of King Brychan, who went to Cornwall as a Christian missionary.

Alternative names: Endelyn, Endelient, Endelyon.