Eidhean mac Cléirigh, ancestor of the Ó hEidhin/Hynes family of County Galway, fl. 800.
Eidhean was a member of the dynasty of Uí Fiachrach Aidhne, and a descendant of Guaire Aidne mac Colmáin (d. 663), Fiachrae mac Eochaid Mugmedon (fl. 5th century) and thus distantly related to the dynasty of Uí Néill. His descendants ruled Aidhne for a time, most notably in the 1090s when Flaithbertaigh Ua Flaithbertaigh seized the kingship of Connacht and installed an Ó hEidhin as a puppet-king for a time.
Eidhean was a kinsman of a number of other men whose descendants also took their surnames from them, such as
and, of course
Though in many cases the relationship between these men was quite distant, Eidhean would have been a contemporary or near-contemporary of almost all of them.
He was killed in battle against Neide mac Onchu, about the year 800.