[W einion, anvil].
Name borne by scores of early Welsh figures of purported historicity (see below), as well as by several historical poets and bards, e.g. Einion ap Gwalchmai (fl. 1203–23), Einion ap Gwgan (fl. 1215), Einion ap Madog ap Rhahawd (fl. 1237), and priests, e.g. Einion Offeiriad (fl. 1330).