Morphology: hafod+yr+ynys
Phonetic: hav-odd-uh-run-niss
Welsh farms traditionally had two sets of dwellings, one for the summer months and one for winter. The summer dwelling or "hafod" was higher in the hills to get the best of the sunshine and the winter dwelling "hendre" was lower in the valley to shelter from the winter winds. Though "ynys" usually refers to an island in the sea, it can also refer to an area of land between two rivers or a simply a river meadow. The village name, therefore means "summer dwelling in the river meadow".