Creuddyn was a medieval commote (Welsh: cwmwd) and, later, a lordship in Ceredigion, Wales. It was located between the rivers Ystwyth and Rheidol, and was one of the three commotes of Cantref Penweddig. The name, of Old Welsh origin, probably refers to the Pen Dinas hill fort, anciently known as Dinas Maelor. The natural centre of the commote was Llanfihangel y Creuddyn where five roads meet at the village.