The official Welsh name, Llanwynell, also found on many maps, is derived from the name of the reputed Saint Gwynell, noted by Lewys Dynn as "Syr Vwniel L. of(f) Wolffs Newton(,) Knight. He accepted the Christian Faith año 188, and erected a church at his own expense." In a list of Welsh parishes circa 1556, and in other later lists, Gwynell is given the parish of Llanwynell or Llanwnell.
