Aha, Welsh place names are strange for sure.
Here is an explanation:
Cwmgwili translates from Welsh into English as "valley of the Gwili" or "valley of the stream/river Gwili."Breakdown of the Welsh NameCwm: Means "valley," "glen," or "hollow" in Welsh.Gwili: Refers to the River Gwili (or a local stream/waterway) in Carmarthenshire, Wales, whose name derives from elements meaning a wild stream or flowing water (gwyllt + lli) or an old Celtic water root (gwy).
