Aenghus Ua Flainn (died 1036) was Abbot of Clonfert. An apparent kinsman, Coinneccám Ua Flainn, was also abbot and died in 1081.
References
Annals of Ulster at CELT: Corpus of Electronic Texts at University College Cork Annals of Tigernach at CELT: Corpus of Electronic Texts at University College Cork Revised edition of McCarthy's synchronisms at Trinity College Dublin. Byrne, Francis John (2001), Irish Kings and High-Kings, Dublin: Four Courts Press,